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Linux/include/linux/sched.h

  1 #ifndef _LINUX_SCHED_H
  2 #define _LINUX_SCHED_H
  3 
  4 #include <uapi/linux/sched.h>
  5 
  6 #include <linux/sched/prio.h>
  7 
  8 
  9 struct sched_param {
 10         int sched_priority;
 11 };
 12 
 13 #include <asm/param.h>  /* for HZ */
 14 
 15 #include <linux/capability.h>
 16 #include <linux/threads.h>
 17 #include <linux/kernel.h>
 18 #include <linux/types.h>
 19 #include <linux/timex.h>
 20 #include <linux/jiffies.h>
 21 #include <linux/plist.h>
 22 #include <linux/rbtree.h>
 23 #include <linux/thread_info.h>
 24 #include <linux/cpumask.h>
 25 #include <linux/errno.h>
 26 #include <linux/nodemask.h>
 27 #include <linux/mm_types.h>
 28 #include <linux/preempt.h>
 29 
 30 #include <asm/page.h>
 31 #include <asm/ptrace.h>
 32 #include <linux/cputime.h>
 33 
 34 #include <linux/smp.h>
 35 #include <linux/sem.h>
 36 #include <linux/shm.h>
 37 #include <linux/signal.h>
 38 #include <linux/compiler.h>
 39 #include <linux/completion.h>
 40 #include <linux/pid.h>
 41 #include <linux/percpu.h>
 42 #include <linux/topology.h>
 43 #include <linux/proportions.h>
 44 #include <linux/seccomp.h>
 45 #include <linux/rcupdate.h>
 46 #include <linux/rculist.h>
 47 #include <linux/rtmutex.h>
 48 
 49 #include <linux/time.h>
 50 #include <linux/param.h>
 51 #include <linux/resource.h>
 52 #include <linux/timer.h>
 53 #include <linux/hrtimer.h>
 54 #include <linux/task_io_accounting.h>
 55 #include <linux/latencytop.h>
 56 #include <linux/cred.h>
 57 #include <linux/llist.h>
 58 #include <linux/uidgid.h>
 59 #include <linux/gfp.h>
 60 #include <linux/magic.h>
 61 #include <linux/cgroup-defs.h>
 62 
 63 #include <asm/processor.h>
 64 
 65 #define SCHED_ATTR_SIZE_VER0    48      /* sizeof first published struct */
 66 
 67 /*
 68  * Extended scheduling parameters data structure.
 69  *
 70  * This is needed because the original struct sched_param can not be
 71  * altered without introducing ABI issues with legacy applications
 72  * (e.g., in sched_getparam()).
 73  *
 74  * However, the possibility of specifying more than just a priority for
 75  * the tasks may be useful for a wide variety of application fields, e.g.,
 76  * multimedia, streaming, automation and control, and many others.
 77  *
 78  * This variant (sched_attr) is meant at describing a so-called
 79  * sporadic time-constrained task. In such model a task is specified by:
 80  *  - the activation period or minimum instance inter-arrival time;
 81  *  - the maximum (or average, depending on the actual scheduling
 82  *    discipline) computation time of all instances, a.k.a. runtime;
 83  *  - the deadline (relative to the actual activation time) of each
 84  *    instance.
 85  * Very briefly, a periodic (sporadic) task asks for the execution of
 86  * some specific computation --which is typically called an instance--
 87  * (at most) every period. Moreover, each instance typically lasts no more
 88  * than the runtime and must be completed by time instant t equal to
 89  * the instance activation time + the deadline.
 90  *
 91  * This is reflected by the actual fields of the sched_attr structure:
 92  *
 93  *  @size               size of the structure, for fwd/bwd compat.
 94  *
 95  *  @sched_policy       task's scheduling policy
 96  *  @sched_flags        for customizing the scheduler behaviour
 97  *  @sched_nice         task's nice value      (SCHED_NORMAL/BATCH)
 98  *  @sched_priority     task's static priority (SCHED_FIFO/RR)
 99  *  @sched_deadline     representative of the task's deadline
100  *  @sched_runtime      representative of the task's runtime
101  *  @sched_period       representative of the task's period
102  *
103  * Given this task model, there are a multiplicity of scheduling algorithms
104  * and policies, that can be used to ensure all the tasks will make their
105  * timing constraints.
106  *
107  * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
108  * only user of this new interface. More information about the algorithm
109  * available in the scheduling class file or in Documentation/.
110  */
111 struct sched_attr {
112         u32 size;
113 
114         u32 sched_policy;
115         u64 sched_flags;
116 
117         /* SCHED_NORMAL, SCHED_BATCH */
118         s32 sched_nice;
119 
120         /* SCHED_FIFO, SCHED_RR */
121         u32 sched_priority;
122 
123         /* SCHED_DEADLINE */
124         u64 sched_runtime;
125         u64 sched_deadline;
126         u64 sched_period;
127 };
128 
129 struct futex_pi_state;
130 struct robust_list_head;
131 struct bio_list;
132 struct fs_struct;
133 struct perf_event_context;
134 struct blk_plug;
135 struct filename;
136 struct nameidata;
137 
138 #define VMACACHE_BITS 2
139 #define VMACACHE_SIZE (1U << VMACACHE_BITS)
140 #define VMACACHE_MASK (VMACACHE_SIZE - 1)
141 
142 /*
143  * These are the constant used to fake the fixed-point load-average
144  * counting. Some notes:
145  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
146  *    a load-average precision of 10 bits integer + 11 bits fractional
147  *  - if you want to count load-averages more often, you need more
148  *    precision, or rounding will get you. With 2-second counting freq,
149  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
150  *    11 bit fractions.
151  */
152 extern unsigned long avenrun[];         /* Load averages */
153 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
154 
155 #define FSHIFT          11              /* nr of bits of precision */
156 #define FIXED_1         (1<<FSHIFT)     /* 1.0 as fixed-point */
157 #define LOAD_FREQ       (5*HZ+1)        /* 5 sec intervals */
158 #define EXP_1           1884            /* 1/exp(5sec/1min) as fixed-point */
159 #define EXP_5           2014            /* 1/exp(5sec/5min) */
160 #define EXP_15          2037            /* 1/exp(5sec/15min) */
161 
162 #define CALC_LOAD(load,exp,n) \
163         load *= exp; \
164         load += n*(FIXED_1-exp); \
165         load >>= FSHIFT;
166 
167 extern unsigned long total_forks;
168 extern int nr_threads;
169 DECLARE_PER_CPU(unsigned long, process_counts);
170 extern int nr_processes(void);
171 extern unsigned long nr_running(void);
172 extern bool single_task_running(void);
173 extern unsigned long nr_iowait(void);
174 extern unsigned long nr_iowait_cpu(int cpu);
175 extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
176 
177 extern void calc_global_load(unsigned long ticks);
178 
179 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
180 extern void update_cpu_load_nohz(void);
181 #else
182 static inline void update_cpu_load_nohz(void) { }
183 #endif
184 
185 extern unsigned long get_parent_ip(unsigned long addr);
186 
187 extern void dump_cpu_task(int cpu);
188 
189 struct seq_file;
190 struct cfs_rq;
191 struct task_group;
192 #ifdef CONFIG_SCHED_DEBUG
193 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
194 extern void proc_sched_set_task(struct task_struct *p);
195 #endif
196 
197 /*
198  * Task state bitmask. NOTE! These bits are also
199  * encoded in fs/proc/array.c: get_task_state().
200  *
201  * We have two separate sets of flags: task->state
202  * is about runnability, while task->exit_state are
203  * about the task exiting. Confusing, but this way
204  * modifying one set can't modify the other one by
205  * mistake.
206  */
207 #define TASK_RUNNING            0
208 #define TASK_INTERRUPTIBLE      1
209 #define TASK_UNINTERRUPTIBLE    2
210 #define __TASK_STOPPED          4
211 #define __TASK_TRACED           8
212 /* in tsk->exit_state */
213 #define EXIT_DEAD               16
214 #define EXIT_ZOMBIE             32
215 #define EXIT_TRACE              (EXIT_ZOMBIE | EXIT_DEAD)
216 /* in tsk->state again */
217 #define TASK_DEAD               64
218 #define TASK_WAKEKILL           128
219 #define TASK_WAKING             256
220 #define TASK_PARKED             512
221 #define TASK_NOLOAD             1024
222 #define TASK_STATE_MAX          2048
223 
224 #define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPN"
225 
226 extern char ___assert_task_state[1 - 2*!!(
227                 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
228 
229 /* Convenience macros for the sake of set_task_state */
230 #define TASK_KILLABLE           (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
231 #define TASK_STOPPED            (TASK_WAKEKILL | __TASK_STOPPED)
232 #define TASK_TRACED             (TASK_WAKEKILL | __TASK_TRACED)
233 
234 #define TASK_IDLE               (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
235 
236 /* Convenience macros for the sake of wake_up */
237 #define TASK_NORMAL             (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
238 #define TASK_ALL                (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
239 
240 /* get_task_state() */
241 #define TASK_REPORT             (TASK_RUNNING | TASK_INTERRUPTIBLE | \
242                                  TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
243                                  __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
244 
245 #define task_is_traced(task)    ((task->state & __TASK_TRACED) != 0)
246 #define task_is_stopped(task)   ((task->state & __TASK_STOPPED) != 0)
247 #define task_is_stopped_or_traced(task) \
248                         ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
249 #define task_contributes_to_load(task)  \
250                                 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
251                                  (task->flags & PF_FROZEN) == 0 && \
252                                  (task->state & TASK_NOLOAD) == 0)
253 
254 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
255 
256 #define __set_task_state(tsk, state_value)                      \
257         do {                                                    \
258                 (tsk)->task_state_change = _THIS_IP_;           \
259                 (tsk)->state = (state_value);                   \
260         } while (0)
261 #define set_task_state(tsk, state_value)                        \
262         do {                                                    \
263                 (tsk)->task_state_change = _THIS_IP_;           \
264                 smp_store_mb((tsk)->state, (state_value));              \
265         } while (0)
266 
267 /*
268  * set_current_state() includes a barrier so that the write of current->state
269  * is correctly serialised wrt the caller's subsequent test of whether to
270  * actually sleep:
271  *
272  *      set_current_state(TASK_UNINTERRUPTIBLE);
273  *      if (do_i_need_to_sleep())
274  *              schedule();
275  *
276  * If the caller does not need such serialisation then use __set_current_state()
277  */
278 #define __set_current_state(state_value)                        \
279         do {                                                    \
280                 current->task_state_change = _THIS_IP_;         \
281                 current->state = (state_value);                 \
282         } while (0)
283 #define set_current_state(state_value)                          \
284         do {                                                    \
285                 current->task_state_change = _THIS_IP_;         \
286                 smp_store_mb(current->state, (state_value));            \
287         } while (0)
288 
289 #else
290 
291 #define __set_task_state(tsk, state_value)              \
292         do { (tsk)->state = (state_value); } while (0)
293 #define set_task_state(tsk, state_value)                \
294         smp_store_mb((tsk)->state, (state_value))
295 
296 /*
297  * set_current_state() includes a barrier so that the write of current->state
298  * is correctly serialised wrt the caller's subsequent test of whether to
299  * actually sleep:
300  *
301  *      set_current_state(TASK_UNINTERRUPTIBLE);
302  *      if (do_i_need_to_sleep())
303  *              schedule();
304  *
305  * If the caller does not need such serialisation then use __set_current_state()
306  */
307 #define __set_current_state(state_value)                \
308         do { current->state = (state_value); } while (0)
309 #define set_current_state(state_value)                  \
310         smp_store_mb(current->state, (state_value))
311 
312 #endif
313 
314 /* Task command name length */
315 #define TASK_COMM_LEN 16
316 
317 #include <linux/spinlock.h>
318 
319 /*
320  * This serializes "schedule()" and also protects
321  * the run-queue from deletions/modifications (but
322  * _adding_ to the beginning of the run-queue has
323  * a separate lock).
324  */
325 extern rwlock_t tasklist_lock;
326 extern spinlock_t mmlist_lock;
327 
328 struct task_struct;
329 
330 #ifdef CONFIG_PROVE_RCU
331 extern int lockdep_tasklist_lock_is_held(void);
332 #endif /* #ifdef CONFIG_PROVE_RCU */
333 
334 extern void sched_init(void);
335 extern void sched_init_smp(void);
336 extern asmlinkage void schedule_tail(struct task_struct *prev);
337 extern void init_idle(struct task_struct *idle, int cpu);
338 extern void init_idle_bootup_task(struct task_struct *idle);
339 
340 extern cpumask_var_t cpu_isolated_map;
341 
342 extern int runqueue_is_locked(int cpu);
343 
344 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
345 extern void nohz_balance_enter_idle(int cpu);
346 extern void set_cpu_sd_state_idle(void);
347 extern int get_nohz_timer_target(void);
348 #else
349 static inline void nohz_balance_enter_idle(int cpu) { }
350 static inline void set_cpu_sd_state_idle(void) { }
351 #endif
352 
353 /*
354  * Only dump TASK_* tasks. (0 for all tasks)
355  */
356 extern void show_state_filter(unsigned long state_filter);
357 
358 static inline void show_state(void)
359 {
360         show_state_filter(0);
361 }
362 
363 extern void show_regs(struct pt_regs *);
364 
365 /*
366  * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
367  * task), SP is the stack pointer of the first frame that should be shown in the back
368  * trace (or NULL if the entire call-chain of the task should be shown).
369  */
370 extern void show_stack(struct task_struct *task, unsigned long *sp);
371 
372 extern void cpu_init (void);
373 extern void trap_init(void);
374 extern void update_process_times(int user);
375 extern void scheduler_tick(void);
376 
377 extern void sched_show_task(struct task_struct *p);
378 
379 #ifdef CONFIG_LOCKUP_DETECTOR
380 extern void touch_softlockup_watchdog(void);
381 extern void touch_softlockup_watchdog_sync(void);
382 extern void touch_all_softlockup_watchdogs(void);
383 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
384                                   void __user *buffer,
385                                   size_t *lenp, loff_t *ppos);
386 extern unsigned int  softlockup_panic;
387 void lockup_detector_init(void);
388 #else
389 static inline void touch_softlockup_watchdog(void)
390 {
391 }
392 static inline void touch_softlockup_watchdog_sync(void)
393 {
394 }
395 static inline void touch_all_softlockup_watchdogs(void)
396 {
397 }
398 static inline void lockup_detector_init(void)
399 {
400 }
401 #endif
402 
403 #ifdef CONFIG_DETECT_HUNG_TASK
404 void reset_hung_task_detector(void);
405 #else
406 static inline void reset_hung_task_detector(void)
407 {
408 }
409 #endif
410 
411 /* Attach to any functions which should be ignored in wchan output. */
412 #define __sched         __attribute__((__section__(".sched.text")))
413 
414 /* Linker adds these: start and end of __sched functions */
415 extern char __sched_text_start[], __sched_text_end[];
416 
417 /* Is this address in the __sched functions? */
418 extern int in_sched_functions(unsigned long addr);
419 
420 #define MAX_SCHEDULE_TIMEOUT    LONG_MAX
421 extern signed long schedule_timeout(signed long timeout);
422 extern signed long schedule_timeout_interruptible(signed long timeout);
423 extern signed long schedule_timeout_killable(signed long timeout);
424 extern signed long schedule_timeout_uninterruptible(signed long timeout);
425 asmlinkage void schedule(void);
426 extern void schedule_preempt_disabled(void);
427 
428 extern long io_schedule_timeout(long timeout);
429 
430 static inline void io_schedule(void)
431 {
432         io_schedule_timeout(MAX_SCHEDULE_TIMEOUT);
433 }
434 
435 struct nsproxy;
436 struct user_namespace;
437 
438 #ifdef CONFIG_MMU
439 extern void arch_pick_mmap_layout(struct mm_struct *mm);
440 extern unsigned long
441 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
442                        unsigned long, unsigned long);
443 extern unsigned long
444 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
445                           unsigned long len, unsigned long pgoff,
446                           unsigned long flags);
447 #else
448 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
449 #endif
450 
451 #define SUID_DUMP_DISABLE       0       /* No setuid dumping */
452 #define SUID_DUMP_USER          1       /* Dump as user of process */
453 #define SUID_DUMP_ROOT          2       /* Dump as root */
454 
455 /* mm flags */
456 
457 /* for SUID_DUMP_* above */
458 #define MMF_DUMPABLE_BITS 2
459 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
460 
461 extern void set_dumpable(struct mm_struct *mm, int value);
462 /*
463  * This returns the actual value of the suid_dumpable flag. For things
464  * that are using this for checking for privilege transitions, it must
465  * test against SUID_DUMP_USER rather than treating it as a boolean
466  * value.
467  */
468 static inline int __get_dumpable(unsigned long mm_flags)
469 {
470         return mm_flags & MMF_DUMPABLE_MASK;
471 }
472 
473 static inline int get_dumpable(struct mm_struct *mm)
474 {
475         return __get_dumpable(mm->flags);
476 }
477 
478 /* coredump filter bits */
479 #define MMF_DUMP_ANON_PRIVATE   2
480 #define MMF_DUMP_ANON_SHARED    3
481 #define MMF_DUMP_MAPPED_PRIVATE 4
482 #define MMF_DUMP_MAPPED_SHARED  5
483 #define MMF_DUMP_ELF_HEADERS    6
484 #define MMF_DUMP_HUGETLB_PRIVATE 7
485 #define MMF_DUMP_HUGETLB_SHARED  8
486 
487 #define MMF_DUMP_FILTER_SHIFT   MMF_DUMPABLE_BITS
488 #define MMF_DUMP_FILTER_BITS    7
489 #define MMF_DUMP_FILTER_MASK \
490         (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
491 #define MMF_DUMP_FILTER_DEFAULT \
492         ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
493          (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
494 
495 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
496 # define MMF_DUMP_MASK_DEFAULT_ELF      (1 << MMF_DUMP_ELF_HEADERS)
497 #else
498 # define MMF_DUMP_MASK_DEFAULT_ELF      0
499 #endif
500                                         /* leave room for more dump flags */
501 #define MMF_VM_MERGEABLE        16      /* KSM may merge identical pages */
502 #define MMF_VM_HUGEPAGE         17      /* set when VM_HUGEPAGE is set on vma */
503 #define MMF_EXE_FILE_CHANGED    18      /* see prctl_set_mm_exe_file() */
504 
505 #define MMF_HAS_UPROBES         19      /* has uprobes */
506 #define MMF_RECALC_UPROBES      20      /* MMF_HAS_UPROBES can be wrong */
507 
508 #define MMF_INIT_MASK           (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
509 
510 struct sighand_struct {
511         atomic_t                count;
512         struct k_sigaction      action[_NSIG];
513         spinlock_t              siglock;
514         wait_queue_head_t       signalfd_wqh;
515 };
516 
517 struct pacct_struct {
518         int                     ac_flag;
519         long                    ac_exitcode;
520         unsigned long           ac_mem;
521         cputime_t               ac_utime, ac_stime;
522         unsigned long           ac_minflt, ac_majflt;
523 };
524 
525 struct cpu_itimer {
526         cputime_t expires;
527         cputime_t incr;
528         u32 error;
529         u32 incr_error;
530 };
531 
532 /**
533  * struct prev_cputime - snaphsot of system and user cputime
534  * @utime: time spent in user mode
535  * @stime: time spent in system mode
536  * @lock: protects the above two fields
537  *
538  * Stores previous user/system time values such that we can guarantee
539  * monotonicity.
540  */
541 struct prev_cputime {
542 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
543         cputime_t utime;
544         cputime_t stime;
545         raw_spinlock_t lock;
546 #endif
547 };
548 
549 static inline void prev_cputime_init(struct prev_cputime *prev)
550 {
551 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
552         prev->utime = prev->stime = 0;
553         raw_spin_lock_init(&prev->lock);
554 #endif
555 }
556 
557 /**
558  * struct task_cputime - collected CPU time counts
559  * @utime:              time spent in user mode, in &cputime_t units
560  * @stime:              time spent in kernel mode, in &cputime_t units
561  * @sum_exec_runtime:   total time spent on the CPU, in nanoseconds
562  *
563  * This structure groups together three kinds of CPU time that are tracked for
564  * threads and thread groups.  Most things considering CPU time want to group
565  * these counts together and treat all three of them in parallel.
566  */
567 struct task_cputime {
568         cputime_t utime;
569         cputime_t stime;
570         unsigned long long sum_exec_runtime;
571 };
572 
573 /* Alternate field names when used to cache expirations. */
574 #define virt_exp        utime
575 #define prof_exp        stime
576 #define sched_exp       sum_exec_runtime
577 
578 #define INIT_CPUTIME    \
579         (struct task_cputime) {                                 \
580                 .utime = 0,                                     \
581                 .stime = 0,                                     \
582                 .sum_exec_runtime = 0,                          \
583         }
584 
585 /*
586  * This is the atomic variant of task_cputime, which can be used for
587  * storing and updating task_cputime statistics without locking.
588  */
589 struct task_cputime_atomic {
590         atomic64_t utime;
591         atomic64_t stime;
592         atomic64_t sum_exec_runtime;
593 };
594 
595 #define INIT_CPUTIME_ATOMIC \
596         (struct task_cputime_atomic) {                          \
597                 .utime = ATOMIC64_INIT(0),                      \
598                 .stime = ATOMIC64_INIT(0),                      \
599                 .sum_exec_runtime = ATOMIC64_INIT(0),           \
600         }
601 
602 #ifdef CONFIG_PREEMPT_COUNT
603 #define PREEMPT_DISABLED        (1 + PREEMPT_ENABLED)
604 #else
605 #define PREEMPT_DISABLED        PREEMPT_ENABLED
606 #endif
607 
608 /*
609  * Disable preemption until the scheduler is running.
610  * Reset by start_kernel()->sched_init()->init_idle().
611  *
612  * We include PREEMPT_ACTIVE to avoid cond_resched() from working
613  * before the scheduler is active -- see should_resched().
614  */
615 #define INIT_PREEMPT_COUNT      (PREEMPT_DISABLED + PREEMPT_ACTIVE)
616 
617 /**
618  * struct thread_group_cputimer - thread group interval timer counts
619  * @cputime_atomic:     atomic thread group interval timers.
620  * @running:            non-zero when there are timers running and
621  *                      @cputime receives updates.
622  *
623  * This structure contains the version of task_cputime, above, that is
624  * used for thread group CPU timer calculations.
625  */
626 struct thread_group_cputimer {
627         struct task_cputime_atomic cputime_atomic;
628         int running;
629 };
630 
631 #include <linux/rwsem.h>
632 struct autogroup;
633 
634 /*
635  * NOTE! "signal_struct" does not have its own
636  * locking, because a shared signal_struct always
637  * implies a shared sighand_struct, so locking
638  * sighand_struct is always a proper superset of
639  * the locking of signal_struct.
640  */
641 struct signal_struct {
642         atomic_t                sigcnt;
643         atomic_t                live;
644         int                     nr_threads;
645         struct list_head        thread_head;
646 
647         wait_queue_head_t       wait_chldexit;  /* for wait4() */
648 
649         /* current thread group signal load-balancing target: */
650         struct task_struct      *curr_target;
651 
652         /* shared signal handling: */
653         struct sigpending       shared_pending;
654 
655         /* thread group exit support */
656         int                     group_exit_code;
657         /* overloaded:
658          * - notify group_exit_task when ->count is equal to notify_count
659          * - everyone except group_exit_task is stopped during signal delivery
660          *   of fatal signals, group_exit_task processes the signal.
661          */
662         int                     notify_count;
663         struct task_struct      *group_exit_task;
664 
665         /* thread group stop support, overloads group_exit_code too */
666         int                     group_stop_count;
667         unsigned int            flags; /* see SIGNAL_* flags below */
668 
669         /*
670          * PR_SET_CHILD_SUBREAPER marks a process, like a service
671          * manager, to re-parent orphan (double-forking) child processes
672          * to this process instead of 'init'. The service manager is
673          * able to receive SIGCHLD signals and is able to investigate
674          * the process until it calls wait(). All children of this
675          * process will inherit a flag if they should look for a
676          * child_subreaper process at exit.
677          */
678         unsigned int            is_child_subreaper:1;
679         unsigned int            has_child_subreaper:1;
680 
681         /* POSIX.1b Interval Timers */
682         int                     posix_timer_id;
683         struct list_head        posix_timers;
684 
685         /* ITIMER_REAL timer for the process */
686         struct hrtimer real_timer;
687         struct pid *leader_pid;
688         ktime_t it_real_incr;
689 
690         /*
691          * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
692          * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
693          * values are defined to 0 and 1 respectively
694          */
695         struct cpu_itimer it[2];
696 
697         /*
698          * Thread group totals for process CPU timers.
699          * See thread_group_cputimer(), et al, for details.
700          */
701         struct thread_group_cputimer cputimer;
702 
703         /* Earliest-expiration cache. */
704         struct task_cputime cputime_expires;
705 
706         struct list_head cpu_timers[3];
707 
708         struct pid *tty_old_pgrp;
709 
710         /* boolean value for session group leader */
711         int leader;
712 
713         struct tty_struct *tty; /* NULL if no tty */
714 
715 #ifdef CONFIG_SCHED_AUTOGROUP
716         struct autogroup *autogroup;
717 #endif
718         /*
719          * Cumulative resource counters for dead threads in the group,
720          * and for reaped dead child processes forked by this group.
721          * Live threads maintain their own counters and add to these
722          * in __exit_signal, except for the group leader.
723          */
724         seqlock_t stats_lock;
725         cputime_t utime, stime, cutime, cstime;
726         cputime_t gtime;
727         cputime_t cgtime;
728         struct prev_cputime prev_cputime;
729         unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
730         unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
731         unsigned long inblock, oublock, cinblock, coublock;
732         unsigned long maxrss, cmaxrss;
733         struct task_io_accounting ioac;
734 
735         /*
736          * Cumulative ns of schedule CPU time fo dead threads in the
737          * group, not including a zombie group leader, (This only differs
738          * from jiffies_to_ns(utime + stime) if sched_clock uses something
739          * other than jiffies.)
740          */
741         unsigned long long sum_sched_runtime;
742 
743         /*
744          * We don't bother to synchronize most readers of this at all,
745          * because there is no reader checking a limit that actually needs
746          * to get both rlim_cur and rlim_max atomically, and either one
747          * alone is a single word that can safely be read normally.
748          * getrlimit/setrlimit use task_lock(current->group_leader) to
749          * protect this instead of the siglock, because they really
750          * have no need to disable irqs.
751          */
752         struct rlimit rlim[RLIM_NLIMITS];
753 
754 #ifdef CONFIG_BSD_PROCESS_ACCT
755         struct pacct_struct pacct;      /* per-process accounting information */
756 #endif
757 #ifdef CONFIG_TASKSTATS
758         struct taskstats *stats;
759 #endif
760 #ifdef CONFIG_AUDIT
761         unsigned audit_tty;
762         unsigned audit_tty_log_passwd;
763         struct tty_audit_buf *tty_audit_buf;
764 #endif
765 #ifdef CONFIG_CGROUPS
766         /*
767          * group_rwsem prevents new tasks from entering the threadgroup and
768          * member tasks from exiting,a more specifically, setting of
769          * PF_EXITING.  fork and exit paths are protected with this rwsem
770          * using threadgroup_change_begin/end().  Users which require
771          * threadgroup to remain stable should use threadgroup_[un]lock()
772          * which also takes care of exec path.  Currently, cgroup is the
773          * only user.
774          */
775         struct rw_semaphore group_rwsem;
776 #endif
777 
778         oom_flags_t oom_flags;
779         short oom_score_adj;            /* OOM kill score adjustment */
780         short oom_score_adj_min;        /* OOM kill score adjustment min value.
781                                          * Only settable by CAP_SYS_RESOURCE. */
782 
783         struct mutex cred_guard_mutex;  /* guard against foreign influences on
784                                          * credential calculations
785                                          * (notably. ptrace) */
786 };
787 
788 /*
789  * Bits in flags field of signal_struct.
790  */
791 #define SIGNAL_STOP_STOPPED     0x00000001 /* job control stop in effect */
792 #define SIGNAL_STOP_CONTINUED   0x00000002 /* SIGCONT since WCONTINUED reap */
793 #define SIGNAL_GROUP_EXIT       0x00000004 /* group exit in progress */
794 #define SIGNAL_GROUP_COREDUMP   0x00000008 /* coredump in progress */
795 /*
796  * Pending notifications to parent.
797  */
798 #define SIGNAL_CLD_STOPPED      0x00000010
799 #define SIGNAL_CLD_CONTINUED    0x00000020
800 #define SIGNAL_CLD_MASK         (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
801 
802 #define SIGNAL_UNKILLABLE       0x00000040 /* for init: ignore fatal signals */
803 
804 /* If true, all threads except ->group_exit_task have pending SIGKILL */
805 static inline int signal_group_exit(const struct signal_struct *sig)
806 {
807         return  (sig->flags & SIGNAL_GROUP_EXIT) ||
808                 (sig->group_exit_task != NULL);
809 }
810 
811 /*
812  * Some day this will be a full-fledged user tracking system..
813  */
814 struct user_struct {
815         atomic_t __count;       /* reference count */
816         atomic_t processes;     /* How many processes does this user have? */
817         atomic_t sigpending;    /* How many pending signals does this user have? */
818 #ifdef CONFIG_INOTIFY_USER
819         atomic_t inotify_watches; /* How many inotify watches does this user have? */
820         atomic_t inotify_devs;  /* How many inotify devs does this user have opened? */
821 #endif
822 #ifdef CONFIG_FANOTIFY
823         atomic_t fanotify_listeners;
824 #endif
825 #ifdef CONFIG_EPOLL
826         atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
827 #endif
828 #ifdef CONFIG_POSIX_MQUEUE
829         /* protected by mq_lock */
830         unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
831 #endif
832         unsigned long locked_shm; /* How many pages of mlocked shm ? */
833 
834 #ifdef CONFIG_KEYS
835         struct key *uid_keyring;        /* UID specific keyring */
836         struct key *session_keyring;    /* UID's default session keyring */
837 #endif
838 
839         /* Hash table maintenance information */
840         struct hlist_node uidhash_node;
841         kuid_t uid;
842 
843 #ifdef CONFIG_PERF_EVENTS
844         atomic_long_t locked_vm;
845 #endif
846 };
847 
848 extern int uids_sysfs_init(void);
849 
850 extern struct user_struct *find_user(kuid_t);
851 
852 extern struct user_struct root_user;
853 #define INIT_USER (&root_user)
854 
855 
856 struct backing_dev_info;
857 struct reclaim_state;
858 
859 #ifdef CONFIG_SCHED_INFO
860 struct sched_info {
861         /* cumulative counters */
862         unsigned long pcount;         /* # of times run on this cpu */
863         unsigned long long run_delay; /* time spent waiting on a runqueue */
864 
865         /* timestamps */
866         unsigned long long last_arrival,/* when we last ran on a cpu */
867                            last_queued; /* when we were last queued to run */
868 };
869 #endif /* CONFIG_SCHED_INFO */
870 
871 #ifdef CONFIG_TASK_DELAY_ACCT
872 struct task_delay_info {
873         spinlock_t      lock;
874         unsigned int    flags;  /* Private per-task flags */
875 
876         /* For each stat XXX, add following, aligned appropriately
877          *
878          * struct timespec XXX_start, XXX_end;
879          * u64 XXX_delay;
880          * u32 XXX_count;
881          *
882          * Atomicity of updates to XXX_delay, XXX_count protected by
883          * single lock above (split into XXX_lock if contention is an issue).
884          */
885 
886         /*
887          * XXX_count is incremented on every XXX operation, the delay
888          * associated with the operation is added to XXX_delay.
889          * XXX_delay contains the accumulated delay time in nanoseconds.
890          */
891         u64 blkio_start;        /* Shared by blkio, swapin */
892         u64 blkio_delay;        /* wait for sync block io completion */
893         u64 swapin_delay;       /* wait for swapin block io completion */
894         u32 blkio_count;        /* total count of the number of sync block */
895                                 /* io operations performed */
896         u32 swapin_count;       /* total count of the number of swapin block */
897                                 /* io operations performed */
898 
899         u64 freepages_start;
900         u64 freepages_delay;    /* wait for memory reclaim */
901         u32 freepages_count;    /* total count of memory reclaim */
902 };
903 #endif  /* CONFIG_TASK_DELAY_ACCT */
904 
905 static inline int sched_info_on(void)
906 {
907 #ifdef CONFIG_SCHEDSTATS
908         return 1;
909 #elif defined(CONFIG_TASK_DELAY_ACCT)
910         extern int delayacct_on;
911         return delayacct_on;
912 #else
913         return 0;
914 #endif
915 }
916 
917 enum cpu_idle_type {
918         CPU_IDLE,
919         CPU_NOT_IDLE,
920         CPU_NEWLY_IDLE,
921         CPU_MAX_IDLE_TYPES
922 };
923 
924 /*
925  * Increase resolution of cpu_capacity calculations
926  */
927 #define SCHED_CAPACITY_SHIFT    10
928 #define SCHED_CAPACITY_SCALE    (1L << SCHED_CAPACITY_SHIFT)
929 
930 /*
931  * Wake-queues are lists of tasks with a pending wakeup, whose
932  * callers have already marked the task as woken internally,
933  * and can thus carry on. A common use case is being able to
934  * do the wakeups once the corresponding user lock as been
935  * released.
936  *
937  * We hold reference to each task in the list across the wakeup,
938  * thus guaranteeing that the memory is still valid by the time
939  * the actual wakeups are performed in wake_up_q().
940  *
941  * One per task suffices, because there's never a need for a task to be
942  * in two wake queues simultaneously; it is forbidden to abandon a task
943  * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is
944  * already in a wake queue, the wakeup will happen soon and the second
945  * waker can just skip it.
946  *
947  * The WAKE_Q macro declares and initializes the list head.
948  * wake_up_q() does NOT reinitialize the list; it's expected to be
949  * called near the end of a function, where the fact that the queue is
950  * not used again will be easy to see by inspection.
951  *
952  * Note that this can cause spurious wakeups. schedule() callers
953  * must ensure the call is done inside a loop, confirming that the
954  * wakeup condition has in fact occurred.
955  */
956 struct wake_q_node {
957         struct wake_q_node *next;
958 };
959 
960 struct wake_q_head {
961         struct wake_q_node *first;
962         struct wake_q_node **lastp;
963 };
964 
965 #define WAKE_Q_TAIL ((struct wake_q_node *) 0x01)
966 
967 #define WAKE_Q(name)                                    \
968         struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
969 
970 extern void wake_q_add(struct wake_q_head *head,
971                        struct task_struct *task);
972 extern void wake_up_q(struct wake_q_head *head);
973 
974 /*
975  * sched-domains (multiprocessor balancing) declarations:
976  */
977 #ifdef CONFIG_SMP
978 #define SD_LOAD_BALANCE         0x0001  /* Do load balancing on this domain. */
979 #define SD_BALANCE_NEWIDLE      0x0002  /* Balance when about to become idle */
980 #define SD_BALANCE_EXEC         0x0004  /* Balance on exec */
981 #define SD_BALANCE_FORK         0x0008  /* Balance on fork, clone */
982 #define SD_BALANCE_WAKE         0x0010  /* Balance on wakeup */
983 #define SD_WAKE_AFFINE          0x0020  /* Wake task to waking CPU */
984 #define SD_SHARE_CPUCAPACITY    0x0080  /* Domain members share cpu power */
985 #define SD_SHARE_POWERDOMAIN    0x0100  /* Domain members share power domain */
986 #define SD_SHARE_PKG_RESOURCES  0x0200  /* Domain members share cpu pkg resources */
987 #define SD_SERIALIZE            0x0400  /* Only a single load balancing instance */
988 #define SD_ASYM_PACKING         0x0800  /* Place busy groups earlier in the domain */
989 #define SD_PREFER_SIBLING       0x1000  /* Prefer to place tasks in a sibling domain */
990 #define SD_OVERLAP              0x2000  /* sched_domains of this level overlap */
991 #define SD_NUMA                 0x4000  /* cross-node balancing */
992 
993 #ifdef CONFIG_SCHED_SMT
994 static inline int cpu_smt_flags(void)
995 {
996         return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
997 }
998 #endif
999 
1000 #ifdef CONFIG_SCHED_MC
1001 static inline int cpu_core_flags(void)
1002 {
1003         return SD_SHARE_PKG_RESOURCES;
1004 }
1005 #endif
1006 
1007 #ifdef CONFIG_NUMA
1008 static inline int cpu_numa_flags(void)
1009 {
1010         return SD_NUMA;
1011 }
1012 #endif
1013 
1014 struct sched_domain_attr {
1015         int relax_domain_level;
1016 };
1017 
1018 #define SD_ATTR_INIT    (struct sched_domain_attr) {    \
1019         .relax_domain_level = -1,                       \
1020 }
1021 
1022 extern int sched_domain_level_max;
1023 
1024 struct sched_group;
1025 
1026 struct sched_domain {
1027         /* These fields must be setup */
1028         struct sched_domain *parent;    /* top domain must be null terminated */
1029         struct sched_domain *child;     /* bottom domain must be null terminated */
1030         struct sched_group *groups;     /* the balancing groups of the domain */
1031         unsigned long min_interval;     /* Minimum balance interval ms */
1032         unsigned long max_interval;     /* Maximum balance interval ms */
1033         unsigned int busy_factor;       /* less balancing by factor if busy */
1034         unsigned int imbalance_pct;     /* No balance until over watermark */
1035         unsigned int cache_nice_tries;  /* Leave cache hot tasks for # tries */
1036         unsigned int busy_idx;
1037         unsigned int idle_idx;
1038         unsigned int newidle_idx;
1039         unsigned int wake_idx;
1040         unsigned int forkexec_idx;
1041         unsigned int smt_gain;
1042 
1043         int nohz_idle;                  /* NOHZ IDLE status */
1044         int flags;                      /* See SD_* */
1045         int level;
1046 
1047         /* Runtime fields. */
1048         unsigned long last_balance;     /* init to jiffies. units in jiffies */
1049         unsigned int balance_interval;  /* initialise to 1. units in ms. */
1050         unsigned int nr_balance_failed; /* initialise to 0 */
1051 
1052         /* idle_balance() stats */
1053         u64 max_newidle_lb_cost;
1054         unsigned long next_decay_max_lb_cost;
1055 
1056 #ifdef CONFIG_SCHEDSTATS
1057         /* load_balance() stats */
1058         unsigned int lb_count[CPU_MAX_IDLE_TYPES];
1059         unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
1060         unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
1061         unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
1062         unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
1063         unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
1064         unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
1065         unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
1066 
1067         /* Active load balancing */
1068         unsigned int alb_count;
1069         unsigned int alb_failed;
1070         unsigned int alb_pushed;
1071 
1072         /* SD_BALANCE_EXEC stats */
1073         unsigned int sbe_count;
1074         unsigned int sbe_balanced;
1075         unsigned int sbe_pushed;
1076 
1077         /* SD_BALANCE_FORK stats */
1078         unsigned int sbf_count;
1079         unsigned int sbf_balanced;
1080         unsigned int sbf_pushed;
1081 
1082         /* try_to_wake_up() stats */
1083         unsigned int ttwu_wake_remote;
1084         unsigned int ttwu_move_affine;
1085         unsigned int ttwu_move_balance;
1086 #endif
1087 #ifdef CONFIG_SCHED_DEBUG
1088         char *name;
1089 #endif
1090         union {
1091                 void *private;          /* used during construction */
1092                 struct rcu_head rcu;    /* used during destruction */
1093         };
1094 
1095         unsigned int span_weight;
1096         /*
1097          * Span of all CPUs in this domain.
1098          *
1099          * NOTE: this field is variable length. (Allocated dynamically
1100          * by attaching extra space to the end of the structure,
1101          * depending on how many CPUs the kernel has booted up with)
1102          */
1103         unsigned long span[0];
1104 };
1105 
1106 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
1107 {
1108         return to_cpumask(sd->span);
1109 }
1110 
1111 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1112                                     struct sched_domain_attr *dattr_new);
1113 
1114 /* Allocate an array of sched domains, for partition_sched_domains(). */
1115 cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
1116 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
1117 
1118 bool cpus_share_cache(int this_cpu, int that_cpu);
1119 
1120 typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
1121 typedef int (*sched_domain_flags_f)(void);
1122 
1123 #define SDTL_OVERLAP    0x01
1124 
1125 struct sd_data {
1126         struct sched_domain **__percpu sd;
1127         struct sched_group **__percpu sg;
1128         struct sched_group_capacity **__percpu sgc;
1129 };
1130 
1131 struct sched_domain_topology_level {
1132         sched_domain_mask_f mask;
1133         sched_domain_flags_f sd_flags;
1134         int                 flags;
1135         int                 numa_level;
1136         struct sd_data      data;
1137 #ifdef CONFIG_SCHED_DEBUG
1138         char                *name;
1139 #endif
1140 };
1141 
1142 extern struct sched_domain_topology_level *sched_domain_topology;
1143 
1144 extern void set_sched_topology(struct sched_domain_topology_level *tl);
1145 extern void wake_up_if_idle(int cpu);
1146 
1147 #ifdef CONFIG_SCHED_DEBUG
1148 # define SD_INIT_NAME(type)             .name = #type
1149 #else
1150 # define SD_INIT_NAME(type)
1151 #endif
1152 
1153 #else /* CONFIG_SMP */
1154 
1155 struct sched_domain_attr;
1156 
1157 static inline void
1158 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1159                         struct sched_domain_attr *dattr_new)
1160 {
1161 }
1162 
1163 static inline bool cpus_share_cache(int this_cpu, int that_cpu)
1164 {
1165         return true;
1166 }
1167 
1168 #endif  /* !CONFIG_SMP */
1169 
1170 
1171 struct io_context;                      /* See blkdev.h */
1172 
1173 
1174 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1175 extern void prefetch_stack(struct task_struct *t);
1176 #else
1177 static inline void prefetch_stack(struct task_struct *t) { }
1178 #endif
1179 
1180 struct audit_context;           /* See audit.c */
1181 struct mempolicy;
1182 struct pipe_inode_info;
1183 struct uts_namespace;
1184 
1185 struct load_weight {
1186         unsigned long weight;
1187         u32 inv_weight;
1188 };
1189 
1190 /*
1191  * The load_avg/util_avg accumulates an infinite geometric series.
1192  * 1) load_avg factors the amount of time that a sched_entity is
1193  * runnable on a rq into its weight. For cfs_rq, it is the aggregated
1194  * such weights of all runnable and blocked sched_entities.
1195  * 2) util_avg factors frequency scaling into the amount of time
1196  * that a sched_entity is running on a CPU, in the range [0..SCHED_LOAD_SCALE].
1197  * For cfs_rq, it is the aggregated such times of all runnable and
1198  * blocked sched_entities.
1199  * The 64 bit load_sum can:
1200  * 1) for cfs_rq, afford 4353082796 (=2^64/47742/88761) entities with
1201  * the highest weight (=88761) always runnable, we should not overflow
1202  * 2) for entity, support any load.weight always runnable
1203  */
1204 struct sched_avg {
1205         u64 last_update_time, load_sum;
1206         u32 util_sum, period_contrib;
1207         unsigned long load_avg, util_avg;
1208 };
1209 
1210 #ifdef CONFIG_SCHEDSTATS
1211 struct sched_statistics {
1212         u64                     wait_start;
1213         u64                     wait_max;
1214         u64                     wait_count;
1215         u64                     wait_sum;
1216         u64                     iowait_count;
1217         u64                     iowait_sum;
1218 
1219         u64                     sleep_start;
1220         u64                     sleep_max;
1221         s64                     sum_sleep_runtime;
1222 
1223         u64                     block_start;
1224         u64                     block_max;
1225         u64                     exec_max;
1226         u64                     slice_max;
1227 
1228         u64                     nr_migrations_cold;
1229         u64                     nr_failed_migrations_affine;
1230         u64                     nr_failed_migrations_running;
1231         u64                     nr_failed_migrations_hot;
1232         u64                     nr_forced_migrations;
1233 
1234         u64                     nr_wakeups;
1235         u64                     nr_wakeups_sync;
1236         u64                     nr_wakeups_migrate;
1237         u64                     nr_wakeups_local;
1238         u64                     nr_wakeups_remote;
1239         u64                     nr_wakeups_affine;
1240         u64                     nr_wakeups_affine_attempts;
1241         u64                     nr_wakeups_passive;
1242         u64                     nr_wakeups_idle;
1243 };
1244 #endif
1245 
1246 struct sched_entity {
1247         struct load_weight      load;           /* for load-balancing */
1248         struct rb_node          run_node;
1249         struct list_head        group_node;
1250         unsigned int            on_rq;
1251 
1252         u64                     exec_start;
1253         u64                     sum_exec_runtime;
1254         u64                     vruntime;
1255         u64                     prev_sum_exec_runtime;
1256 
1257         u64                     nr_migrations;
1258 
1259 #ifdef CONFIG_SCHEDSTATS
1260         struct sched_statistics statistics;
1261 #endif
1262 
1263 #ifdef CONFIG_FAIR_GROUP_SCHED
1264         int                     depth;
1265         struct sched_entity     *parent;
1266         /* rq on which this entity is (to be) queued: */
1267         struct cfs_rq           *cfs_rq;
1268         /* rq "owned" by this entity/group: */
1269         struct cfs_rq           *my_q;
1270 #endif
1271 
1272 #ifdef CONFIG_SMP
1273         /* Per entity load average tracking */
1274         struct sched_avg        avg;
1275 #endif
1276 };
1277 
1278 struct sched_rt_entity {
1279         struct list_head run_list;
1280         unsigned long timeout;
1281         unsigned long watchdog_stamp;
1282         unsigned int time_slice;
1283 
1284         struct sched_rt_entity *back;
1285 #ifdef CONFIG_RT_GROUP_SCHED
1286         struct sched_rt_entity  *parent;
1287         /* rq on which this entity is (to be) queued: */
1288         struct rt_rq            *rt_rq;
1289         /* rq "owned" by this entity/group: */
1290         struct rt_rq            *my_q;
1291 #endif
1292 };
1293 
1294 struct sched_dl_entity {
1295         struct rb_node  rb_node;
1296 
1297         /*
1298          * Original scheduling parameters. Copied here from sched_attr
1299          * during sched_setattr(), they will remain the same until
1300          * the next sched_setattr().
1301          */
1302         u64 dl_runtime;         /* maximum runtime for each instance    */
1303         u64 dl_deadline;        /* relative deadline of each instance   */
1304         u64 dl_period;          /* separation of two instances (period) */
1305         u64 dl_bw;              /* dl_runtime / dl_deadline             */
1306 
1307         /*
1308          * Actual scheduling parameters. Initialized with the values above,
1309          * they are continously updated during task execution. Note that
1310          * the remaining runtime could be < 0 in case we are in overrun.
1311          */
1312         s64 runtime;            /* remaining runtime for this instance  */
1313         u64 deadline;           /* absolute deadline for this instance  */
1314         unsigned int flags;     /* specifying the scheduler behaviour   */
1315 
1316         /*
1317          * Some bool flags:
1318          *
1319          * @dl_throttled tells if we exhausted the runtime. If so, the
1320          * task has to wait for a replenishment to be performed at the
1321          * next firing of dl_timer.
1322          *
1323          * @dl_new tells if a new instance arrived. If so we must
1324          * start executing it with full runtime and reset its absolute
1325          * deadline;
1326          *
1327          * @dl_boosted tells if we are boosted due to DI. If so we are
1328          * outside bandwidth enforcement mechanism (but only until we
1329          * exit the critical section);
1330          *
1331          * @dl_yielded tells if task gave up the cpu before consuming
1332          * all its available runtime during the last job.
1333          */
1334         int dl_throttled, dl_new, dl_boosted, dl_yielded;
1335 
1336         /*
1337          * Bandwidth enforcement timer. Each -deadline task has its
1338          * own bandwidth to be enforced, thus we need one timer per task.
1339          */
1340         struct hrtimer dl_timer;
1341 };
1342 
1343 union rcu_special {
1344         struct {
1345                 bool blocked;
1346                 bool need_qs;
1347         } b;
1348         short s;
1349 };
1350 struct rcu_node;
1351 
1352 enum perf_event_task_context {
1353         perf_invalid_context = -1,
1354         perf_hw_context = 0,
1355         perf_sw_context,
1356         perf_nr_task_contexts,
1357 };
1358 
1359 /* Track pages that require TLB flushes */
1360 struct tlbflush_unmap_batch {
1361         /*
1362          * Each bit set is a CPU that potentially has a TLB entry for one of
1363          * the PFNs being flushed. See set_tlb_ubc_flush_pending().
1364          */
1365         struct cpumask cpumask;
1366 
1367         /* True if any bit in cpumask is set */
1368         bool flush_required;
1369 
1370         /*
1371          * If true then the PTE was dirty when unmapped. The entry must be
1372          * flushed before IO is initiated or a stale TLB entry potentially
1373          * allows an update without redirtying the page.
1374          */
1375         bool writable;
1376 };
1377 
1378 struct task_struct {
1379         volatile long state;    /* -1 unrunnable, 0 runnable, >0 stopped */
1380         void *stack;
1381         atomic_t usage;
1382         unsigned int flags;     /* per process flags, defined below */
1383         unsigned int ptrace;
1384 
1385 #ifdef CONFIG_SMP
1386         struct llist_node wake_entry;
1387         int on_cpu;
1388         unsigned int wakee_flips;
1389         unsigned long wakee_flip_decay_ts;
1390         struct task_struct *last_wakee;
1391 
1392         int wake_cpu;
1393 #endif
1394         int on_rq;
1395 
1396         int prio, static_prio, normal_prio;
1397         unsigned int rt_priority;
1398         const struct sched_class *sched_class;
1399         struct sched_entity se;
1400         struct sched_rt_entity rt;
1401 #ifdef CONFIG_CGROUP_SCHED
1402         struct task_group *sched_task_group;
1403 #endif
1404         struct sched_dl_entity dl;
1405 
1406 #ifdef CONFIG_PREEMPT_NOTIFIERS
1407         /* list of struct preempt_notifier: */
1408         struct hlist_head preempt_notifiers;
1409 #endif
1410 
1411 #ifdef CONFIG_BLK_DEV_IO_TRACE
1412         unsigned int btrace_seq;
1413 #endif
1414 
1415         unsigned int policy;
1416         int nr_cpus_allowed;
1417         cpumask_t cpus_allowed;
1418 
1419 #ifdef CONFIG_PREEMPT_RCU
1420         int rcu_read_lock_nesting;
1421         union rcu_special rcu_read_unlock_special;
1422         struct list_head rcu_node_entry;
1423         struct rcu_node *rcu_blocked_node;
1424 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1425 #ifdef CONFIG_TASKS_RCU
1426         unsigned long rcu_tasks_nvcsw;
1427         bool rcu_tasks_holdout;
1428         struct list_head rcu_tasks_holdout_list;
1429         int rcu_tasks_idle_cpu;
1430 #endif /* #ifdef CONFIG_TASKS_RCU */
1431 
1432 #ifdef CONFIG_SCHED_INFO
1433         struct sched_info sched_info;
1434 #endif
1435 
1436         struct list_head tasks;
1437 #ifdef CONFIG_SMP
1438         struct plist_node pushable_tasks;
1439         struct rb_node pushable_dl_tasks;
1440 #endif
1441 
1442         struct mm_struct *mm, *active_mm;
1443         /* per-thread vma caching */
1444         u32 vmacache_seqnum;
1445         struct vm_area_struct *vmacache[VMACACHE_SIZE];
1446 #if defined(SPLIT_RSS_COUNTING)
1447         struct task_rss_stat    rss_stat;
1448 #endif
1449 /* task state */
1450         int exit_state;
1451         int exit_code, exit_signal;
1452         int pdeath_signal;  /*  The signal sent when the parent dies  */
1453         unsigned long jobctl;   /* JOBCTL_*, siglock protected */
1454 
1455         /* Used for emulating ABI behavior of previous Linux versions */
1456         unsigned int personality;
1457 
1458         unsigned in_execve:1;   /* Tell the LSMs that the process is doing an
1459                                  * execve */
1460         unsigned in_iowait:1;
1461 
1462         /* Revert to default priority/policy when forking */
1463         unsigned sched_reset_on_fork:1;
1464         unsigned sched_contributes_to_load:1;
1465         unsigned sched_migrated:1;
1466 
1467 #ifdef CONFIG_MEMCG_KMEM
1468         unsigned memcg_kmem_skip_account:1;
1469 #endif
1470 #ifdef CONFIG_COMPAT_BRK
1471         unsigned brk_randomized:1;
1472 #endif
1473 
1474         unsigned long atomic_flags; /* Flags needing atomic access. */
1475 
1476         struct restart_block restart_block;
1477 
1478         pid_t pid;
1479         pid_t tgid;
1480 
1481 #ifdef CONFIG_CC_STACKPROTECTOR
1482         /* Canary value for the -fstack-protector gcc feature */
1483         unsigned long stack_canary;
1484 #endif
1485         /*
1486          * pointers to (original) parent process, youngest child, younger sibling,
1487          * older sibling, respectively.  (p->father can be replaced with
1488          * p->real_parent->pid)
1489          */
1490         struct task_struct __rcu *real_parent; /* real parent process */
1491         struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
1492         /*
1493          * children/sibling forms the list of my natural children
1494          */
1495         struct list_head children;      /* list of my children */
1496         struct list_head sibling;       /* linkage in my parent's children list */
1497         struct task_struct *group_leader;       /* threadgroup leader */
1498 
1499         /*
1500          * ptraced is the list of tasks this task is using ptrace on.
1501          * This includes both natural children and PTRACE_ATTACH targets.
1502          * p->ptrace_entry is p's link on the p->parent->ptraced list.
1503          */
1504         struct list_head ptraced;
1505         struct list_head ptrace_entry;
1506 
1507         /* PID/PID hash table linkage. */
1508         struct pid_link pids[PIDTYPE_MAX];
1509         struct list_head thread_group;
1510         struct list_head thread_node;
1511 
1512         struct completion *vfork_done;          /* for vfork() */
1513         int __user *set_child_tid;              /* CLONE_CHILD_SETTID */
1514         int __user *clear_child_tid;            /* CLONE_CHILD_CLEARTID */
1515 
1516         cputime_t utime, stime, utimescaled, stimescaled;
1517         cputime_t gtime;
1518         struct prev_cputime prev_cputime;
1519 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1520         seqlock_t vtime_seqlock;
1521         unsigned long long vtime_snap;
1522         enum {
1523                 VTIME_SLEEPING = 0,
1524                 VTIME_USER,
1525                 VTIME_SYS,
1526         } vtime_snap_whence;
1527 #endif
1528         unsigned long nvcsw, nivcsw; /* context switch counts */
1529         u64 start_time;         /* monotonic time in nsec */
1530         u64 real_start_time;    /* boot based time in nsec */
1531 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1532         unsigned long min_flt, maj_flt;
1533 
1534         struct task_cputime cputime_expires;
1535         struct list_head cpu_timers[3];
1536 
1537 /* process credentials */
1538         const struct cred __rcu *real_cred; /* objective and real subjective task
1539                                          * credentials (COW) */
1540         const struct cred __rcu *cred;  /* effective (overridable) subjective task
1541                                          * credentials (COW) */
1542         char comm[TASK_COMM_LEN]; /* executable name excluding path
1543                                      - access with [gs]et_task_comm (which lock
1544                                        it with task_lock())
1545                                      - initialized normally by setup_new_exec */
1546 /* file system info */
1547         struct nameidata *nameidata;
1548 #ifdef CONFIG_SYSVIPC
1549 /* ipc stuff */
1550         struct sysv_sem sysvsem;
1551         struct sysv_shm sysvshm;
1552 #endif
1553 #ifdef CONFIG_DETECT_HUNG_TASK
1554 /* hung task detection */
1555         unsigned long last_switch_count;
1556 #endif
1557 /* filesystem information */
1558         struct fs_struct *fs;
1559 /* open file information */
1560         struct files_struct *files;
1561 /* namespaces */
1562         struct nsproxy *nsproxy;
1563 /* signal handlers */
1564         struct signal_struct *signal;
1565         struct sighand_struct *sighand;
1566 
1567         sigset_t blocked, real_blocked;
1568         sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1569         struct sigpending pending;
1570 
1571         unsigned long sas_ss_sp;
1572         size_t sas_ss_size;
1573         int (*notifier)(void *priv);
1574         void *notifier_data;
1575         sigset_t *notifier_mask;
1576         struct callback_head *task_works;
1577 
1578         struct audit_context *audit_context;
1579 #ifdef CONFIG_AUDITSYSCALL
1580         kuid_t loginuid;
1581         unsigned int sessionid;
1582 #endif
1583         struct seccomp seccomp;
1584 
1585 /* Thread group tracking */
1586         u32 parent_exec_id;
1587         u32 self_exec_id;
1588 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1589  * mempolicy */
1590         spinlock_t alloc_lock;
1591 
1592         /* Protection of the PI data structures: */
1593         raw_spinlock_t pi_lock;
1594 
1595         struct wake_q_node wake_q;
1596 
1597 #ifdef CONFIG_RT_MUTEXES
1598         /* PI waiters blocked on a rt_mutex held by this task */
1599         struct rb_root pi_waiters;
1600         struct rb_node *pi_waiters_leftmost;
1601         /* Deadlock detection and priority inheritance handling */
1602         struct rt_mutex_waiter *pi_blocked_on;
1603 #endif
1604 
1605 #ifdef CONFIG_DEBUG_MUTEXES
1606         /* mutex deadlock detection */
1607         struct mutex_waiter *blocked_on;
1608 #endif
1609 #ifdef CONFIG_TRACE_IRQFLAGS
1610         unsigned int irq_events;
1611         unsigned long hardirq_enable_ip;
1612         unsigned long hardirq_disable_ip;
1613         unsigned int hardirq_enable_event;
1614         unsigned int hardirq_disable_event;
1615         int hardirqs_enabled;
1616         int hardirq_context;
1617         unsigned long softirq_disable_ip;
1618         unsigned long softirq_enable_ip;
1619         unsigned int softirq_disable_event;
1620         unsigned int softirq_enable_event;
1621         int softirqs_enabled;
1622         int softirq_context;
1623 #endif
1624 #ifdef CONFIG_LOCKDEP
1625 # define MAX_LOCK_DEPTH 48UL
1626         u64 curr_chain_key;
1627         int lockdep_depth;
1628         unsigned int lockdep_recursion;
1629         struct held_lock held_locks[MAX_LOCK_DEPTH];
1630         gfp_t lockdep_reclaim_gfp;
1631 #endif
1632 
1633 /* journalling filesystem info */
1634         void *journal_info;
1635 
1636 /* stacked block device info */
1637         struct bio_list *bio_list;
1638 
1639 #ifdef CONFIG_BLOCK
1640 /* stack plugging */
1641         struct blk_plug *plug;
1642 #endif
1643 
1644 /* VM state */
1645         struct reclaim_state *reclaim_state;
1646 
1647         struct backing_dev_info *backing_dev_info;
1648 
1649         struct io_context *io_context;
1650 
1651         unsigned long ptrace_message;
1652         siginfo_t *last_siginfo; /* For ptrace use.  */
1653         struct task_io_accounting ioac;
1654 #if defined(CONFIG_TASK_XACCT)
1655         u64 acct_rss_mem1;      /* accumulated rss usage */
1656         u64 acct_vm_mem1;       /* accumulated virtual memory usage */
1657         cputime_t acct_timexpd; /* stime + utime since last update */
1658 #endif
1659 #ifdef CONFIG_CPUSETS
1660         nodemask_t mems_allowed;        /* Protected by alloc_lock */
1661         seqcount_t mems_allowed_seq;    /* Seqence no to catch updates */
1662         int cpuset_mem_spread_rotor;
1663         int cpuset_slab_spread_rotor;
1664 #endif
1665 #ifdef CONFIG_CGROUPS
1666         /* Control Group info protected by css_set_lock */
1667         struct css_set __rcu *cgroups;
1668         /* cg_list protected by css_set_lock and tsk->alloc_lock */
1669         struct list_head cg_list;
1670 #endif
1671 #ifdef CONFIG_FUTEX
1672         struct robust_list_head __user *robust_list;
1673 #ifdef CONFIG_COMPAT
1674         struct compat_robust_list_head __user *compat_robust_list;
1675 #endif
1676         struct list_head pi_state_list;
1677         struct futex_pi_state *pi_state_cache;
1678 #endif
1679 #ifdef CONFIG_PERF_EVENTS
1680         struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1681         struct mutex perf_event_mutex;
1682         struct list_head perf_event_list;
1683 #endif
1684 #ifdef CONFIG_DEBUG_PREEMPT
1685         unsigned long preempt_disable_ip;
1686 #endif
1687 #ifdef CONFIG_NUMA
1688         struct mempolicy *mempolicy;    /* Protected by alloc_lock */
1689         short il_next;
1690         short pref_node_fork;
1691 #endif
1692 #ifdef CONFIG_NUMA_BALANCING
1693         int numa_scan_seq;
1694         unsigned int numa_scan_period;
1695         unsigned int numa_scan_period_max;
1696         int numa_preferred_nid;
1697         unsigned long numa_migrate_retry;
1698         u64 node_stamp;                 /* migration stamp  */
1699         u64 last_task_numa_placement;
1700         u64 last_sum_exec_runtime;
1701         struct callback_head numa_work;
1702 
1703         struct list_head numa_entry;
1704         struct numa_group *numa_group;
1705 
1706         /*
1707          * numa_faults is an array split into four regions:
1708          * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1709          * in this precise order.
1710          *
1711          * faults_memory: Exponential decaying average of faults on a per-node
1712          * basis. Scheduling placement decisions are made based on these
1713          * counts. The values remain static for the duration of a PTE scan.
1714          * faults_cpu: Track the nodes the process was running on when a NUMA
1715          * hinting fault was incurred.
1716          * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1717          * during the current scan window. When the scan completes, the counts
1718          * in faults_memory and faults_cpu decay and these values are copied.
1719          */
1720         unsigned long *numa_faults;
1721         unsigned long total_numa_faults;
1722 
1723         /*
1724          * numa_faults_locality tracks if faults recorded during the last
1725          * scan window were remote/local or failed to migrate. The task scan
1726          * period is adapted based on the locality of the faults with different
1727          * weights depending on whether they were shared or private faults
1728          */
1729         unsigned long numa_faults_locality[3];
1730 
1731         unsigned long numa_pages_migrated;
1732 #endif /* CONFIG_NUMA_BALANCING */
1733 
1734 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
1735         struct tlbflush_unmap_batch tlb_ubc;
1736 #endif
1737 
1738         struct rcu_head rcu;
1739 
1740         /*
1741          * cache last used pipe for splice
1742          */
1743         struct pipe_inode_info *splice_pipe;
1744 
1745         struct page_frag task_frag;
1746 
1747 #ifdef  CONFIG_TASK_DELAY_ACCT
1748         struct task_delay_info *delays;
1749 #endif
1750 #ifdef CONFIG_FAULT_INJECTION
1751         int make_it_fail;
1752 #endif
1753         /*
1754          * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1755          * balance_dirty_pages() for some dirty throttling pause
1756          */
1757         int nr_dirtied;
1758         int nr_dirtied_pause;
1759         unsigned long dirty_paused_when; /* start of a write-and-pause period */
1760 
1761 #ifdef CONFIG_LATENCYTOP
1762         int latency_record_count;
1763         struct latency_record latency_record[LT_SAVECOUNT];
1764 #endif
1765         /*
1766          * time slack values; these are used to round up poll() and
1767          * select() etc timeout values. These are in nanoseconds.
1768          */
1769         unsigned long timer_slack_ns;
1770         unsigned long default_timer_slack_ns;
1771 
1772 #ifdef CONFIG_KASAN
1773         unsigned int kasan_depth;
1774 #endif
1775 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1776         /* Index of current stored address in ret_stack */
1777         int curr_ret_stack;
1778         /* Stack of return addresses for return function tracing */
1779         struct ftrace_ret_stack *ret_stack;
1780         /* time stamp for last schedule */
1781         unsigned long long ftrace_timestamp;
1782         /*
1783          * Number of functions that haven't been traced
1784          * because of depth overrun.
1785          */
1786         atomic_t trace_overrun;
1787         /* Pause for the tracing */
1788         atomic_t tracing_graph_pause;
1789 #endif
1790 #ifdef CONFIG_TRACING
1791         /* state flags for use by tracers */
1792         unsigned long trace;
1793         /* bitmask and counter of trace recursion */
1794         unsigned long trace_recursion;
1795 #endif /* CONFIG_TRACING */
1796 #ifdef CONFIG_MEMCG
1797         struct memcg_oom_info {
1798                 struct mem_cgroup *memcg;
1799                 gfp_t gfp_mask;
1800                 int order;
1801                 unsigned int may_oom:1;
1802         } memcg_oom;
1803 #endif
1804 #ifdef CONFIG_UPROBES
1805         struct uprobe_task *utask;
1806 #endif
1807 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1808         unsigned int    sequential_io;
1809         unsigned int    sequential_io_avg;
1810 #endif
1811 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1812         unsigned long   task_state_change;
1813 #endif
1814         int pagefault_disabled;
1815 /* CPU-specific state of this task */
1816         struct thread_struct thread;
1817 /*
1818  * WARNING: on x86, 'thread_struct' contains a variable-sized
1819  * structure.  It *MUST* be at the end of 'task_struct'.
1820  *
1821  * Do not put anything below here!
1822  */
1823 };
1824 
1825 #ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT
1826 extern int arch_task_struct_size __read_mostly;
1827 #else
1828 # define arch_task_struct_size (sizeof(struct task_struct))
1829 #endif
1830 
1831 /* Future-safe accessor for struct task_struct's cpus_allowed. */
1832 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1833 
1834 #define TNF_MIGRATED    0x01
1835 #define TNF_NO_GROUP    0x02
1836 #define TNF_SHARED      0x04
1837 #define TNF_FAULT_LOCAL 0x08
1838 #define TNF_MIGRATE_FAIL 0x10
1839 
1840 #ifdef CONFIG_NUMA_BALANCING
1841 extern void task_numa_fault(int last_node, int node, int pages, int flags);
1842 extern pid_t task_numa_group_id(struct task_struct *p);
1843 extern void set_numabalancing_state(bool enabled);
1844 extern void task_numa_free(struct task_struct *p);
1845 extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page,
1846                                         int src_nid, int dst_cpu);
1847 #else
1848 static inline void task_numa_fault(int last_node, int node, int pages,
1849                                    int flags)
1850 {
1851 }
1852 static inline pid_t task_numa_group_id(struct task_struct *p)
1853 {
1854         return 0;
1855 }
1856 static inline void set_numabalancing_state(bool enabled)
1857 {
1858 }
1859 static inline void task_numa_free(struct task_struct *p)
1860 {
1861 }
1862 static inline bool should_numa_migrate_memory(struct task_struct *p,
1863                                 struct page *page, int src_nid, int dst_cpu)
1864 {
1865         return true;
1866 }
1867 #endif
1868 
1869 static inline struct pid *task_pid(struct task_struct *task)
1870 {
1871         return task->pids[PIDTYPE_PID].pid;
1872 }
1873 
1874 static inline struct pid *task_tgid(struct task_struct *task)
1875 {
1876         return task->group_leader->pids[PIDTYPE_PID].pid;
1877 }
1878 
1879 /*
1880  * Without tasklist or rcu lock it is not safe to dereference
1881  * the result of task_pgrp/task_session even if task == current,
1882  * we can race with another thread doing sys_setsid/sys_setpgid.
1883  */
1884 static inline struct pid *task_pgrp(struct task_struct *task)
1885 {
1886         return task->group_leader->pids[PIDTYPE_PGID].pid;
1887 }
1888 
1889 static inline struct pid *task_session(struct task_struct *task)
1890 {
1891         return task->group_leader->pids[PIDTYPE_SID].pid;
1892 }
1893 
1894 struct pid_namespace;
1895 
1896 /*
1897  * the helpers to get the task's different pids as they are seen
1898  * from various namespaces
1899  *
1900  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1901  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1902  *                     current.
1903  * task_xid_nr_ns()  : id seen from the ns specified;
1904  *
1905  * set_task_vxid()   : assigns a virtual id to a task;
1906  *
1907  * see also pid_nr() etc in include/linux/pid.h
1908  */
1909 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1910                         struct pid_namespace *ns);
1911 
1912 static inline pid_t task_pid_nr(struct task_struct *tsk)
1913 {
1914         return tsk->pid;
1915 }
1916 
1917 static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1918                                         struct pid_namespace *ns)
1919 {
1920         return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1921 }
1922 
1923 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1924 {
1925         return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1926 }
1927 
1928 
1929 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1930 {
1931         return tsk->tgid;
1932 }
1933 
1934 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1935 
1936 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1937 {
1938         return pid_vnr(task_tgid(tsk));
1939 }
1940 
1941 
1942 static inline int pid_alive(const struct task_struct *p);
1943 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1944 {
1945         pid_t pid = 0;
1946 
1947         rcu_read_lock();
1948         if (pid_alive(tsk))
1949                 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1950         rcu_read_unlock();
1951 
1952         return pid;
1953 }
1954 
1955 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1956 {
1957         return task_ppid_nr_ns(tsk, &init_pid_ns);
1958 }
1959 
1960 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1961                                         struct pid_namespace *ns)
1962 {
1963         return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1964 }
1965 
1966 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1967 {
1968         return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1969 }
1970 
1971 
1972 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1973                                         struct pid_namespace *ns)
1974 {
1975         return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1976 }
1977 
1978 static inline pid_t task_session_vnr(struct task_struct *tsk)
1979 {
1980         return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1981 }
1982 
1983 /* obsolete, do not use */
1984 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1985 {
1986         return task_pgrp_nr_ns(tsk, &init_pid_ns);
1987 }
1988 
1989 /**
1990  * pid_alive - check that a task structure is not stale
1991  * @p: Task structure to be checked.
1992  *
1993  * Test if a process is not yet dead (at most zombie state)
1994  * If pid_alive fails, then pointers within the task structure
1995  * can be stale and must not be dereferenced.
1996  *
1997  * Return: 1 if the process is alive. 0 otherwise.
1998  */
1999 static inline int pid_alive(const struct task_struct *p)
2000 {
2001         return p->pids[PIDTYPE_PID].pid != NULL;
2002 }
2003 
2004 /**
2005  * is_global_init - check if a task structure is init
2006  * @tsk: Task structure to be checked.
2007  *
2008  * Check if a task structure is the first user space task the kernel created.
2009  *
2010  * Return: 1 if the task structure is init. 0 otherwise.
2011  */
2012 static inline int is_global_init(struct task_struct *tsk)
2013 {
2014         return tsk->pid == 1;
2015 }
2016 
2017 extern struct pid *cad_pid;
2018 
2019 extern void free_task(struct task_struct *tsk);
2020 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
2021 
2022 extern void __put_task_struct(struct task_struct *t);
2023 
2024 static inline void put_task_struct(struct task_struct *t)
2025 {
2026         if (atomic_dec_and_test(&t->usage))
2027                 __put_task_struct(t);
2028 }
2029 
2030 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
2031 extern void task_cputime(struct task_struct *t,
2032                          cputime_t *utime, cputime_t *stime);
2033 extern void task_cputime_scaled(struct task_struct *t,
2034                                 cputime_t *utimescaled, cputime_t *stimescaled);
2035 extern cputime_t task_gtime(struct task_struct *t);
2036 #else
2037 static inline void task_cputime(struct task_struct *t,
2038                                 cputime_t *utime, cputime_t *stime)
2039 {
2040         if (utime)
2041                 *utime = t->utime;
2042         if (stime)
2043                 *stime = t->stime;
2044 }
2045 
2046 static inline void task_cputime_scaled(struct task_struct *t,
2047                                        cputime_t *utimescaled,
2048                                        cputime_t *stimescaled)
2049 {
2050         if (utimescaled)
2051                 *utimescaled = t->utimescaled;
2052         if (stimescaled)
2053                 *stimescaled = t->stimescaled;
2054 }
2055 
2056 static inline cputime_t task_gtime(struct task_struct *t)
2057 {
2058         return t->gtime;
2059 }
2060 #endif
2061 extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2062 extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2063 
2064 /*
2065  * Per process flags
2066  */
2067 #define PF_EXITING      0x00000004      /* getting shut down */
2068 #define PF_EXITPIDONE   0x00000008      /* pi exit done on shut down */
2069 #define PF_VCPU         0x00000010      /* I'm a virtual CPU */
2070 #define PF_WQ_WORKER    0x00000020      /* I'm a workqueue worker */
2071 #define PF_FORKNOEXEC   0x00000040      /* forked but didn't exec */
2072 #define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
2073 #define PF_SUPERPRIV    0x00000100      /* used super-user privileges */
2074 #define PF_DUMPCORE     0x00000200      /* dumped core */
2075 #define PF_SIGNALED     0x00000400      /* killed by a signal */
2076 #define PF_MEMALLOC     0x00000800      /* Allocating memory */
2077 #define PF_NPROC_EXCEEDED 0x00001000    /* set_user noticed that RLIMIT_NPROC was exceeded */
2078 #define PF_USED_MATH    0x00002000      /* if unset the fpu must be initialized before use */
2079 #define PF_USED_ASYNC   0x00004000      /* used async_schedule*(), used by module init */
2080 #define PF_NOFREEZE     0x00008000      /* this thread should not be frozen */
2081 #define PF_FROZEN       0x00010000      /* frozen for system suspend */
2082 #define PF_FSTRANS      0x00020000      /* inside a filesystem transaction */
2083 #define PF_KSWAPD       0x00040000      /* I am kswapd */
2084 #define PF_MEMALLOC_NOIO 0x00080000     /* Allocating memory without IO involved */
2085 #define PF_LESS_THROTTLE 0x00100000     /* Throttle me less: I clean memory */
2086 #define PF_KTHREAD      0x00200000      /* I am a kernel thread */
2087 #define PF_RANDOMIZE    0x00400000      /* randomize virtual address space */
2088 #define PF_SWAPWRITE    0x00800000      /* Allowed to write to swap */
2089 #define PF_NO_SETAFFINITY 0x04000000    /* Userland is not allowed to meddle with cpus_allowed */
2090 #define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
2091 #define PF_MUTEX_TESTER 0x20000000      /* Thread belongs to the rt mutex tester */
2092 #define PF_FREEZER_SKIP 0x40000000      /* Freezer should not count it as freezable */
2093 #define PF_SUSPEND_TASK 0x80000000      /* this thread called freeze_processes and should not be frozen */
2094 
2095 /*
2096  * Only the _current_ task can read/write to tsk->flags, but other
2097  * tasks can access tsk->flags in readonly mode for example
2098  * with tsk_used_math (like during threaded core dumping).
2099  * There is however an exception to this rule during ptrace
2100  * or during fork: the ptracer task is allowed to write to the
2101  * child->flags of its traced child (same goes for fork, the parent
2102  * can write to the child->flags), because we're guaranteed the
2103  * child is not running and in turn not changing child->flags
2104  * at the same time the parent does it.
2105  */
2106 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
2107 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
2108 #define clear_used_math() clear_stopped_child_used_math(current)
2109 #define set_used_math() set_stopped_child_used_math(current)
2110 #define conditional_stopped_child_used_math(condition, child) \
2111         do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
2112 #define conditional_used_math(condition) \
2113         conditional_stopped_child_used_math(condition, current)
2114 #define copy_to_stopped_child_used_math(child) \
2115         do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
2116 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
2117 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
2118 #define used_math() tsk_used_math(current)
2119 
2120 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags
2121  * __GFP_FS is also cleared as it implies __GFP_IO.
2122  */
2123 static inline gfp_t memalloc_noio_flags(gfp_t flags)
2124 {
2125         if (unlikely(current->flags & PF_MEMALLOC_NOIO))
2126                 flags &= ~(__GFP_IO | __GFP_FS);
2127         return flags;
2128 }
2129 
2130 static inline unsigned int memalloc_noio_save(void)
2131 {
2132         unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
2133         current->flags |= PF_MEMALLOC_NOIO;
2134         return flags;
2135 }
2136 
2137 static inline void memalloc_noio_restore(unsigned int flags)
2138 {
2139         current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
2140 }
2141 
2142 /* Per-process atomic flags. */
2143 #define PFA_NO_NEW_PRIVS 0      /* May not gain new privileges. */
2144 #define PFA_SPREAD_PAGE  1      /* Spread page cache over cpuset */
2145 #define PFA_SPREAD_SLAB  2      /* Spread some slab caches over cpuset */
2146 
2147 
2148 #define TASK_PFA_TEST(name, func)                                       \
2149         static inline bool task_##func(struct task_struct *p)           \
2150         { return test_bit(PFA_##name, &p->atomic_flags); }
2151 #define TASK_PFA_SET(name, func)                                        \
2152         static inline void task_set_##func(struct task_struct *p)       \
2153         { set_bit(PFA_##name, &p->atomic_flags); }
2154 #define TASK_PFA_CLEAR(name, func)                                      \
2155         static inline void task_clear_##func(struct task_struct *p)     \
2156         { clear_bit(PFA_##name, &p->atomic_flags); }
2157 
2158 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
2159 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
2160 
2161 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
2162 TASK_PFA_SET(SPREAD_PAGE, spread_page)
2163 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
2164 
2165 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
2166 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
2167 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
2168 
2169 /*
2170  * task->jobctl flags
2171  */
2172 #define JOBCTL_STOP_SIGMASK     0xffff  /* signr of the last group stop */
2173 
2174 #define JOBCTL_STOP_DEQUEUED_BIT 16     /* stop signal dequeued */
2175 #define JOBCTL_STOP_PENDING_BIT 17      /* task should stop for group stop */
2176 #define JOBCTL_STOP_CONSUME_BIT 18      /* consume group stop count */
2177 #define JOBCTL_TRAP_STOP_BIT    19      /* trap for STOP */
2178 #define JOBCTL_TRAP_NOTIFY_BIT  20      /* trap for NOTIFY */
2179 #define JOBCTL_TRAPPING_BIT     21      /* switching to TRACED */
2180 #define JOBCTL_LISTENING_BIT    22      /* ptracer is listening for events */
2181 
2182 #define JOBCTL_STOP_DEQUEUED    (1UL << JOBCTL_STOP_DEQUEUED_BIT)
2183 #define JOBCTL_STOP_PENDING     (1UL << JOBCTL_STOP_PENDING_BIT)
2184 #define JOBCTL_STOP_CONSUME     (1UL << JOBCTL_STOP_CONSUME_BIT)
2185 #define JOBCTL_TRAP_STOP        (1UL << JOBCTL_TRAP_STOP_BIT)
2186 #define JOBCTL_TRAP_NOTIFY      (1UL << JOBCTL_TRAP_NOTIFY_BIT)
2187 #define JOBCTL_TRAPPING         (1UL << JOBCTL_TRAPPING_BIT)
2188 #define JOBCTL_LISTENING        (1UL << JOBCTL_LISTENING_BIT)
2189 
2190 #define JOBCTL_TRAP_MASK        (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
2191 #define JOBCTL_PENDING_MASK     (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
2192 
2193 extern bool task_set_jobctl_pending(struct task_struct *task,
2194                                     unsigned long mask);
2195 extern void task_clear_jobctl_trapping(struct task_struct *task);
2196 extern void task_clear_jobctl_pending(struct task_struct *task,
2197                                       unsigned long mask);
2198 
2199 static inline void rcu_copy_process(struct task_struct *p)
2200 {
2201 #ifdef CONFIG_PREEMPT_RCU
2202         p->rcu_read_lock_nesting = 0;
2203         p->rcu_read_unlock_special.s = 0;
2204         p->rcu_blocked_node = NULL;
2205         INIT_LIST_HEAD(&p->rcu_node_entry);
2206 #endif /* #ifdef CONFIG_PREEMPT_RCU */
2207 #ifdef CONFIG_TASKS_RCU
2208         p->rcu_tasks_holdout = false;
2209         INIT_LIST_HEAD(&p->rcu_tasks_holdout_list);
2210         p->rcu_tasks_idle_cpu = -1;
2211 #endif /* #ifdef CONFIG_TASKS_RCU */
2212 }
2213 
2214 static inline void tsk_restore_flags(struct task_struct *task,
2215                                 unsigned long orig_flags, unsigned long flags)
2216 {
2217         task->flags &= ~flags;
2218         task->flags |= orig_flags & flags;
2219 }
2220 
2221 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur,
2222                                      const struct cpumask *trial);
2223 extern int task_can_attach(struct task_struct *p,
2224                            const struct cpumask *cs_cpus_allowed);
2225 #ifdef CONFIG_SMP
2226 extern void do_set_cpus_allowed(struct task_struct *p,
2227                                const struct cpumask *new_mask);
2228 
2229 extern int set_cpus_allowed_ptr(struct task_struct *p,
2230                                 const struct cpumask *new_mask);
2231 #else
2232 static inline void do_set_cpus_allowed(struct task_struct *p,
2233                                       const struct cpumask *new_mask)
2234 {
2235 }
2236 static inline int set_cpus_allowed_ptr(struct task_struct *p,
2237                                        const struct cpumask *new_mask)
2238 {
2239         if (!cpumask_test_cpu(0, new_mask))
2240                 return -EINVAL;
2241         return 0;
2242 }
2243 #endif
2244 
2245 #ifdef CONFIG_NO_HZ_COMMON
2246 void calc_load_enter_idle(void);
2247 void calc_load_exit_idle(void);
2248 #else
2249 static inline void calc_load_enter_idle(void) { }
2250 static inline void calc_load_exit_idle(void) { }
2251 #endif /* CONFIG_NO_HZ_COMMON */
2252 
2253 /*
2254  * Do not use outside of architecture code which knows its limitations.
2255  *
2256  * sched_clock() has no promise of monotonicity or bounded drift between
2257  * CPUs, use (which you should not) requires disabling IRQs.
2258  *
2259  * Please use one of the three interfaces below.
2260  */
2261 extern unsigned long long notrace sched_clock(void);
2262 /*
2263  * See the comment in kernel/sched/clock.c
2264  */
2265 extern u64 cpu_clock(int cpu);
2266 extern u64 local_clock(void);
2267 extern u64 running_clock(void);
2268 extern u64 sched_clock_cpu(int cpu);
2269 
2270 
2271 extern void sched_clock_init(void);
2272 
2273 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
2274 static inline void sched_clock_tick(void)
2275 {
2276 }
2277 
2278 static inline void sched_clock_idle_sleep_event(void)
2279 {
2280 }
2281 
2282 static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
2283 {
2284 }
2285 #else
2286 /*
2287  * Architectures can set this to 1 if they have specified
2288  * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
2289  * but then during bootup it turns out that sched_clock()
2290  * is reliable after all:
2291  */
2292 extern int sched_clock_stable(void);
2293 extern void set_sched_clock_stable(void);
2294 extern void clear_sched_clock_stable(void);
2295 
2296 extern void sched_clock_tick(void);
2297 extern void sched_clock_idle_sleep_event(void);
2298 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2299 #endif
2300 
2301 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2302 /*
2303  * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
2304  * The reason for this explicit opt-in is not to have perf penalty with
2305  * slow sched_clocks.
2306  */
2307 extern void enable_sched_clock_irqtime(void);
2308 extern void disable_sched_clock_irqtime(void);
2309 #else
2310 static inline void enable_sched_clock_irqtime(void) {}
2311 static inline void disable_sched_clock_irqtime(void) {}
2312 #endif
2313 
2314 extern unsigned long long
2315 task_sched_runtime(struct task_struct *task);
2316 
2317 /* sched_exec is called by processes performing an exec */
2318 #ifdef CONFIG_SMP
2319 extern void sched_exec(void);
2320 #else
2321 #define sched_exec()   {}
2322 #endif
2323 
2324 extern void sched_clock_idle_sleep_event(void);
2325 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2326 
2327 #ifdef CONFIG_HOTPLUG_CPU
2328 extern void idle_task_exit(void);
2329 #else
2330 static inline void idle_task_exit(void) {}
2331 #endif
2332 
2333 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
2334 extern void wake_up_nohz_cpu(int cpu);
2335 #else
2336 static inline void wake_up_nohz_cpu(int cpu) { }
2337 #endif
2338 
2339 #ifdef CONFIG_NO_HZ_FULL
2340 extern bool sched_can_stop_tick(void);
2341 extern u64 scheduler_tick_max_deferment(void);
2342 #else
2343 static inline bool sched_can_stop_tick(void) { return false; }
2344 #endif
2345 
2346 #ifdef CONFIG_SCHED_AUTOGROUP
2347 extern void sched_autogroup_create_attach(struct task_struct *p);
2348 extern void sched_autogroup_detach(struct task_struct *p);
2349 extern void sched_autogroup_fork(struct signal_struct *sig);
2350 extern void sched_autogroup_exit(struct signal_struct *sig);
2351 #ifdef CONFIG_PROC_FS
2352 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2353 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
2354 #endif
2355 #else
2356 static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2357 static inline void sched_autogroup_detach(struct task_struct *p) { }
2358 static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2359 static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2360 #endif
2361 
2362 extern int yield_to(struct task_struct *p, bool preempt);
2363 extern void set_user_nice(struct task_struct *p, long nice);
2364 extern int task_prio(const struct task_struct *p);
2365 /**
2366  * task_nice - return the nice value of a given task.
2367  * @p: the task in question.
2368  *
2369  * Return: The nice value [ -20 ... 0 ... 19 ].
2370  */
2371 static inline int task_nice(const struct task_struct *p)
2372 {
2373         return PRIO_TO_NICE((p)->static_prio);
2374 }
2375 extern int can_nice(const struct task_struct *p, const int nice);
2376 extern int task_curr(const struct task_struct *p);
2377 extern int idle_cpu(int cpu);
2378 extern int sched_setscheduler(struct task_struct *, int,
2379                               const struct sched_param *);
2380 extern int sched_setscheduler_nocheck(struct task_struct *, int,
2381                                       const struct sched_param *);
2382 extern int sched_setattr(struct task_struct *,
2383                          const struct sched_attr *);
2384 extern struct task_struct *idle_task(int cpu);
2385 /**
2386  * is_idle_task - is the specified task an idle task?
2387  * @p: the task in question.
2388  *
2389  * Return: 1 if @p is an idle task. 0 otherwise.
2390  */
2391 static inline bool is_idle_task(const struct task_struct *p)
2392 {
2393         return p->pid == 0;
2394 }
2395 extern struct task_struct *curr_task(int cpu);
2396 extern void set_curr_task(int cpu, struct task_struct *p);
2397 
2398 void yield(void);
2399 
2400 union thread_union {
2401         struct thread_info thread_info;
2402         unsigned long stack[THREAD_SIZE/sizeof(long)];
2403 };
2404 
2405 #ifndef __HAVE_ARCH_KSTACK_END
2406 static inline int kstack_end(void *addr)
2407 {
2408         /* Reliable end of stack detection:
2409          * Some APM bios versions misalign the stack
2410          */
2411         return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2412 }
2413 #endif
2414 
2415 extern union thread_union init_thread_union;
2416 extern struct task_struct init_task;
2417 
2418 extern struct   mm_struct init_mm;
2419 
2420 extern struct pid_namespace init_pid_ns;
2421 
2422 /*
2423  * find a task by one of its numerical ids
2424  *
2425  * find_task_by_pid_ns():
2426  *      finds a task by its pid in the specified namespace
2427  * find_task_by_vpid():
2428  *      finds a task by its virtual pid
2429  *
2430  * see also find_vpid() etc in include/linux/pid.h
2431  */
2432 
2433 extern struct task_struct *find_task_by_vpid(pid_t nr);
2434 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2435                 struct pid_namespace *ns);
2436 
2437 /* per-UID process charging. */
2438 extern struct user_struct * alloc_uid(kuid_t);
2439 static inline struct user_struct *get_uid(struct user_struct *u)
2440 {
2441         atomic_inc(&u->__count);
2442         return u;
2443 }
2444 extern void free_uid(struct user_struct *);
2445 
2446 #include <asm/current.h>
2447 
2448 extern void xtime_update(unsigned long ticks);
2449 
2450 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2451 extern int wake_up_process(struct task_struct *tsk);
2452 extern void wake_up_new_task(struct task_struct *tsk);
2453 #ifdef CONFIG_SMP
2454  extern void kick_process(struct task_struct *tsk);
2455 #else
2456  static inline void kick_process(struct task_struct *tsk) { }
2457 #endif
2458 extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
2459 extern void sched_dead(struct task_struct *p);
2460 
2461 extern void proc_caches_init(void);
2462 extern void flush_signals(struct task_struct *);
2463 extern void ignore_signals(struct task_struct *);
2464 extern void flush_signal_handlers(struct task_struct *, int force_default);
2465 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2466 
2467 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2468 {
2469         unsigned long flags;
2470         int ret;
2471 
2472         spin_lock_irqsave(&tsk->sighand->siglock, flags);
2473         ret = dequeue_signal(tsk, mask, info);
2474         spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2475 
2476         return ret;
2477 }
2478 
2479 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2480                               sigset_t *mask);
2481 extern void unblock_all_signals(void);
2482 extern void release_task(struct task_struct * p);
2483 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2484 extern int force_sigsegv(int, struct task_struct *);
2485 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2486 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2487 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2488 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
2489                                 const struct cred *, u32);
2490 extern int kill_pgrp(struct pid *pid, int sig, int priv);
2491 extern int kill_pid(struct pid *pid, int sig, int priv);
2492 extern int kill_proc_info(int, struct siginfo *, pid_t);
2493 extern __must_check bool do_notify_parent(struct task_struct *, int);
2494 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2495 extern void force_sig(int, struct task_struct *);
2496 extern int send_sig(int, struct task_struct *, int);
2497 extern int zap_other_threads(struct task_struct *p);
2498 extern struct sigqueue *sigqueue_alloc(void);
2499 extern void sigqueue_free(struct sigqueue *);
2500 extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2501 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2502 
2503 static inline void restore_saved_sigmask(void)
2504 {
2505         if (test_and_clear_restore_sigmask())
2506                 __set_current_blocked(&current->saved_sigmask);
2507 }
2508 
2509 static inline sigset_t *sigmask_to_save(void)
2510 {
2511         sigset_t *res = &current->blocked;
2512         if (unlikely(test_restore_sigmask()))
2513                 res = &current->saved_sigmask;
2514         return res;
2515 }
2516 
2517 static inline int kill_cad_pid(int sig, int priv)
2518 {
2519         return kill_pid(cad_pid, sig, priv);
2520 }
2521 
2522 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
2523 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
2524 #define SEND_SIG_PRIV   ((struct siginfo *) 1)
2525 #define SEND_SIG_FORCED ((struct siginfo *) 2)
2526 
2527 /*
2528  * True if we are on the alternate signal stack.
2529  */
2530 static inline int on_sig_stack(unsigned long sp)
2531 {
2532 #ifdef CONFIG_STACK_GROWSUP
2533         return sp >= current->sas_ss_sp &&
2534                 sp - current->sas_ss_sp < current->sas_ss_size;
2535 #else
2536         return sp > current->sas_ss_sp &&
2537                 sp - current->sas_ss_sp <= current->sas_ss_size;
2538 #endif
2539 }
2540 
2541 static inline int sas_ss_flags(unsigned long sp)
2542 {
2543         if (!current->sas_ss_size)
2544                 return SS_DISABLE;
2545 
2546         return on_sig_stack(sp) ? SS_ONSTACK : 0;
2547 }
2548 
2549 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
2550 {
2551         if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
2552 #ifdef CONFIG_STACK_GROWSUP
2553                 return current->sas_ss_sp;
2554 #else
2555                 return current->sas_ss_sp + current->sas_ss_size;
2556 #endif
2557         return sp;
2558 }
2559 
2560 /*
2561  * Routines for handling mm_structs
2562  */
2563 extern struct mm_struct * mm_alloc(void);
2564 
2565 /* mmdrop drops the mm and the page tables */
2566 extern void __mmdrop(struct mm_struct *);
2567 static inline void mmdrop(struct mm_struct * mm)
2568 {
2569         if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2570                 __mmdrop(mm);
2571 }
2572 
2573 /* mmput gets rid of the mappings and all user-space */
2574 extern void mmput(struct mm_struct *);
2575 /* Grab a reference to a task's mm, if it is not already going away */
2576 extern struct mm_struct *get_task_mm(struct task_struct *task);
2577 /*
2578  * Grab a reference to a task's mm, if it is not already going away
2579  * and ptrace_may_access with the mode parameter passed to it
2580  * succeeds.
2581  */
2582 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
2583 /* Remove the current tasks stale references to the old mm_struct */
2584 extern void mm_release(struct task_struct *, struct mm_struct *);
2585 
2586 #ifdef CONFIG_HAVE_COPY_THREAD_TLS
2587 extern int copy_thread_tls(unsigned long, unsigned long, unsigned long,
2588                         struct task_struct *, unsigned long);
2589 #else
2590 extern int copy_thread(unsigned long, unsigned long, unsigned long,
2591                         struct task_struct *);
2592 
2593 /* Architectures that haven't opted into copy_thread_tls get the tls argument
2594  * via pt_regs, so ignore the tls argument passed via C. */
2595 static inline int copy_thread_tls(
2596                 unsigned long clone_flags, unsigned long sp, unsigned long arg,
2597                 struct task_struct *p, unsigned long tls)
2598 {
2599         return copy_thread(clone_flags, sp, arg, p);
2600 }
2601 #endif
2602 extern void flush_thread(void);
2603 extern void exit_thread(void);
2604 
2605 extern void exit_files(struct task_struct *);
2606 extern void __cleanup_sighand(struct sighand_struct *);
2607 
2608 extern void exit_itimers(struct signal_struct *);
2609 extern void flush_itimer_signals(void);
2610 
2611 extern void do_group_exit(int);
2612 
2613 extern int do_execve(struct filename *,
2614                      const char __user * const __user *,
2615                      const char __user * const __user *);
2616 extern int do_execveat(int, struct filename *,
2617                        const char __user * const __user *,
2618                        const char __user * const __user *,
2619                        int);
2620 extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long);
2621 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2622 struct task_struct *fork_idle(int);
2623 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
2624 
2625 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
2626 static inline void set_task_comm(struct task_struct *tsk, const char *from)
2627 {
2628         __set_task_comm(tsk, from, false);
2629 }
2630 extern char *get_task_comm(char *to, struct task_struct *tsk);
2631 
2632 #ifdef CONFIG_SMP
2633 void scheduler_ipi(void);
2634 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2635 #else
2636 static inline void scheduler_ipi(void) { }
2637 static inline unsigned long wait_task_inactive(struct task_struct *p,
2638                                                long match_state)
2639 {
2640         return 1;
2641 }
2642 #endif
2643 
2644 #define tasklist_empty() \
2645         list_empty(&init_task.tasks)
2646 
2647 #define next_task(p) \
2648         list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2649 
2650 #define for_each_process(p) \
2651         for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2652 
2653 extern bool current_is_single_threaded(void);
2654 
2655 /*
2656  * Careful: do_each_thread/while_each_thread is a double loop so
2657  *          'break' will not work as expected - use goto instead.
2658  */
2659 #define do_each_thread(g, t) \
2660         for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2661 
2662 #define while_each_thread(g, t) \
2663         while ((t = next_thread(t)) != g)
2664 
2665 #define __for_each_thread(signal, t)    \
2666         list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
2667 
2668 #define for_each_thread(p, t)           \
2669         __for_each_thread((p)->signal, t)
2670 
2671 /* Careful: this is a double loop, 'break' won't work as expected. */
2672 #define for_each_process_thread(p, t)   \
2673         for_each_process(p) for_each_thread(p, t)
2674 
2675 static inline int get_nr_threads(struct task_struct *tsk)
2676 {
2677         return tsk->signal->nr_threads;
2678 }
2679 
2680 static inline bool thread_group_leader(struct task_struct *p)
2681 {
2682         return p->exit_signal >= 0;
2683 }
2684 
2685 /* Do to the insanities of de_thread it is possible for a process
2686  * to have the pid of the thread group leader without actually being
2687  * the thread group leader.  For iteration through the pids in proc
2688  * all we care about is that we have a task with the appropriate
2689  * pid, we don't actually care if we have the right task.
2690  */
2691 static inline bool has_group_leader_pid(struct task_struct *p)
2692 {
2693         return task_pid(p) == p->signal->leader_pid;
2694 }
2695 
2696 static inline
2697 bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
2698 {
2699         return p1->signal == p2->signal;
2700 }
2701 
2702 static inline struct task_struct *next_thread(const struct task_struct *p)
2703 {
2704         return list_entry_rcu(p->thread_group.next,
2705                               struct task_struct, thread_group);
2706 }
2707 
2708 static inline int thread_group_empty(struct task_struct *p)
2709 {
2710         return list_empty(&p->thread_group);
2711 }
2712 
2713 #define delay_group_leader(p) \
2714                 (thread_group_leader(p) && !thread_group_empty(p))
2715 
2716 /*
2717  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2718  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2719  * pins the final release of task.io_context.  Also protects ->cpuset and
2720  * ->cgroup.subsys[]. And ->vfork_done.
2721  *
2722  * Nests both inside and outside of read_lock(&tasklist_lock).
2723  * It must not be nested with write_lock_irq(&tasklist_lock),
2724  * neither inside nor outside.
2725  */
2726 static inline void task_lock(struct task_struct *p)
2727 {
2728         spin_lock(&p->alloc_lock);
2729 }
2730 
2731 static inline void task_unlock(struct task_struct *p)
2732 {
2733         spin_unlock(&p->alloc_lock);
2734 }
2735 
2736 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2737                                                         unsigned long *flags);
2738 
2739 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2740                                                        unsigned long *flags)
2741 {
2742         struct sighand_struct *ret;
2743 
2744         ret = __lock_task_sighand(tsk, flags);
2745         (void)__cond_lock(&tsk->sighand->siglock, ret);
2746         return ret;
2747 }
2748 
2749 static inline void unlock_task_sighand(struct task_struct *tsk,
2750                                                 unsigned long *flags)
2751 {
2752         spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2753 }
2754 
2755 /**
2756  * threadgroup_change_begin - mark the beginning of changes to a threadgroup
2757  * @tsk: task causing the changes
2758  *
2759  * All operations which modify a threadgroup - a new thread joining the
2760  * group, death of a member thread (the assertion of PF_EXITING) and
2761  * exec(2) dethreading the process and replacing the leader - are wrapped
2762  * by threadgroup_change_{begin|end}().  This is to provide a place which
2763  * subsystems needing threadgroup stability can hook into for
2764  * synchronization.
2765  */
2766 static inline void threadgroup_change_begin(struct task_struct *tsk)
2767 {
2768         might_sleep();
2769         cgroup_threadgroup_change_begin(tsk);
2770 }
2771 
2772 /**
2773  * threadgroup_change_end - mark the end of changes to a threadgroup
2774  * @tsk: task causing the changes
2775  *
2776  * See threadgroup_change_begin().
2777  */
2778 static inline void threadgroup_change_end(struct task_struct *tsk)
2779 {
2780         cgroup_threadgroup_change_end(tsk);
2781 }
2782 
2783 #ifndef __HAVE_THREAD_FUNCTIONS
2784 
2785 #define task_thread_info(task)  ((struct thread_info *)(task)->stack)
2786 #define task_stack_page(task)   ((task)->stack)
2787 
2788 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2789 {
2790         *task_thread_info(p) = *task_thread_info(org);
2791         task_thread_info(p)->task = p;
2792 }
2793 
2794 /*
2795  * Return the address of the last usable long on the stack.
2796  *
2797  * When the stack grows down, this is just above the thread
2798  * info struct. Going any lower will corrupt the threadinfo.
2799  *
2800  * When the stack grows up, this is the highest address.
2801  * Beyond that position, we corrupt data on the next page.
2802  */
2803 static inline unsigned long *end_of_stack(struct task_struct *p)
2804 {
2805 #ifdef CONFIG_STACK_GROWSUP
2806         return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
2807 #else
2808         return (unsigned long *)(task_thread_info(p) + 1);
2809 #endif
2810 }
2811 
2812 #endif
2813 #define task_stack_end_corrupted(task) \
2814                 (*(end_of_stack(task)) != STACK_END_MAGIC)
2815 
2816 static inline int object_is_on_stack(void *obj)
2817 {
2818         void *stack = task_stack_page(current);
2819 
2820         return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2821 }
2822 
2823 extern void thread_info_cache_init(void);
2824 
2825 #ifdef CONFIG_DEBUG_STACK_USAGE
2826 static inline unsigned long stack_not_used(struct task_struct *p)
2827 {
2828         unsigned long *n = end_of_stack(p);
2829 
2830         do {    /* Skip over canary */
2831                 n++;
2832         } while (!*n);
2833 
2834         return (unsigned long)n - (unsigned long)end_of_stack(p);
2835 }
2836 #endif
2837 extern void set_task_stack_end_magic(struct task_struct *tsk);
2838 
2839 /* set thread flags in other task's structures
2840  * - see asm/thread_info.h for TIF_xxxx flags available
2841  */
2842 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2843 {
2844         set_ti_thread_flag(task_thread_info(tsk), flag);
2845 }
2846 
2847 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2848 {
2849         clear_ti_thread_flag(task_thread_info(tsk), flag);
2850 }
2851 
2852 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2853 {
2854         return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2855 }
2856 
2857 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2858 {
2859         return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2860 }
2861 
2862 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2863 {
2864         return test_ti_thread_flag(task_thread_info(tsk), flag);
2865 }
2866 
2867 static inline void set_tsk_need_resched(struct task_struct *tsk)
2868 {
2869         set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2870 }
2871 
2872 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2873 {
2874         clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2875 }
2876 
2877 static inline int test_tsk_need_resched(struct task_struct *tsk)
2878 {
2879         return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2880 }
2881 
2882 static inline int restart_syscall(void)
2883 {
2884         set_tsk_thread_flag(current, TIF_SIGPENDING);
2885         return -ERESTARTNOINTR;
2886 }
2887 
2888 static inline int signal_pending(struct task_struct *p)
2889 {
2890         return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2891 }
2892 
2893 static inline int __fatal_signal_pending(struct task_struct *p)
2894 {
2895         return unlikely(sigismember(&p->pending.signal, SIGKILL));
2896 }
2897 
2898 static inline int fatal_signal_pending(struct task_struct *p)
2899 {
2900         return signal_pending(p) && __fatal_signal_pending(p);
2901 }
2902 
2903 static inline int signal_pending_state(long state, struct task_struct *p)
2904 {
2905         if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2906                 return 0;
2907         if (!signal_pending(p))
2908                 return 0;
2909 
2910         return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2911 }
2912 
2913 /*
2914  * cond_resched() and cond_resched_lock(): latency reduction via
2915  * explicit rescheduling in places that are safe. The return
2916  * value indicates whether a reschedule was done in fact.
2917  * cond_resched_lock() will drop the spinlock before scheduling,
2918  * cond_resched_softirq() will enable bhs before scheduling.
2919  */
2920 extern int _cond_resched(void);
2921 
2922 #define cond_resched() ({                       \
2923         ___might_sleep(__FILE__, __LINE__, 0);  \
2924         _cond_resched();                        \
2925 })
2926 
2927 extern int __cond_resched_lock(spinlock_t *lock);
2928 
2929 #define cond_resched_lock(lock) ({                              \
2930         ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2931         __cond_resched_lock(lock);                              \
2932 })
2933 
2934 extern int __cond_resched_softirq(void);
2935 
2936 #define cond_resched_softirq() ({                                       \
2937         ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);     \
2938         __cond_resched_softirq();                                       \
2939 })
2940 
2941 static inline void cond_resched_rcu(void)
2942 {
2943 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2944         rcu_read_unlock();
2945         cond_resched();
2946         rcu_read_lock();
2947 #endif
2948 }
2949 
2950 /*
2951  * Does a critical section need to be broken due to another
2952  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2953  * but a general need for low latency)
2954  */
2955 static inline int spin_needbreak(spinlock_t *lock)
2956 {
2957 #ifdef CONFIG_PREEMPT
2958         return spin_is_contended(lock);
2959 #else
2960         return 0;
2961 #endif
2962 }
2963 
2964 /*
2965  * Idle thread specific functions to determine the need_resched
2966  * polling state.
2967  */
2968 #ifdef TIF_POLLING_NRFLAG
2969 static inline int tsk_is_polling(struct task_struct *p)
2970 {
2971         return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
2972 }
2973 
2974 static inline void __current_set_polling(void)
2975 {
2976         set_thread_flag(TIF_POLLING_NRFLAG);
2977 }
2978 
2979 static inline bool __must_check current_set_polling_and_test(void)
2980 {
2981         __current_set_polling();
2982 
2983         /*
2984          * Polling state must be visible before we test NEED_RESCHED,
2985          * paired by resched_curr()
2986          */
2987         smp_mb__after_atomic();
2988 
2989         return unlikely(tif_need_resched());
2990 }
2991 
2992 static inline void __current_clr_polling(void)
2993 {
2994         clear_thread_flag(TIF_POLLING_NRFLAG);
2995 }
2996 
2997 static inline bool __must_check current_clr_polling_and_test(void)
2998 {
2999         __current_clr_polling();
3000 
3001         /*
3002          * Polling state must be visible before we test NEED_RESCHED,
3003          * paired by resched_curr()
3004          */
3005         smp_mb__after_atomic();
3006 
3007         return unlikely(tif_need_resched());
3008 }
3009 
3010 #else
3011 static inline int tsk_is_polling(struct task_struct *p) { return 0; }
3012 static inline void __current_set_polling(void) { }
3013 static inline void __current_clr_polling(void) { }
3014 
3015 static inline bool __must_check current_set_polling_and_test(void)
3016 {
3017         return unlikely(tif_need_resched());
3018 }
3019 static inline bool __must_check current_clr_polling_and_test(void)
3020 {
3021         return unlikely(tif_need_resched());
3022 }
3023 #endif
3024 
3025 static inline void current_clr_polling(void)
3026 {
3027         __current_clr_polling();
3028 
3029         /*
3030          * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
3031          * Once the bit is cleared, we'll get IPIs with every new
3032          * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
3033          * fold.
3034          */
3035         smp_mb(); /* paired with resched_curr() */
3036 
3037         preempt_fold_need_resched();
3038 }
3039 
3040 static __always_inline bool need_resched(void)
3041 {
3042         return unlikely(tif_need_resched());
3043 }
3044 
3045 /*
3046  * Thread group CPU time accounting.
3047  */
3048 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
3049 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
3050 
3051 /*
3052  * Reevaluate whether the task has signals pending delivery.
3053  * Wake the task if so.
3054  * This is required every time the blocked sigset_t changes.
3055  * callers must hold sighand->siglock.
3056  */
3057 extern void recalc_sigpending_and_wake(struct task_struct *t);
3058 extern void recalc_sigpending(void);
3059 
3060 extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
3061 
3062 static inline void signal_wake_up(struct task_struct *t, bool resume)
3063 {
3064         signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
3065 }
3066 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
3067 {
3068         signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
3069 }
3070 
3071 /*
3072  * Wrappers for p->thread_info->cpu access. No-op on UP.
3073  */
3074 #ifdef CONFIG_SMP
3075 
3076 static inline unsigned int task_cpu(const struct task_struct *p)
3077 {
3078         return task_thread_info(p)->cpu;
3079 }
3080 
3081 static inline int task_node(const struct task_struct *p)
3082 {
3083         return cpu_to_node(task_cpu(p));
3084 }
3085 
3086 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
3087 
3088 #else
3089 
3090 static inline unsigned int task_cpu(const struct task_struct *p)
3091 {
3092         return 0;
3093 }
3094 
3095 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
3096 {
3097 }
3098 
3099 #endif /* CONFIG_SMP */
3100 
3101 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
3102 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
3103 
3104 #ifdef CONFIG_CGROUP_SCHED
3105 extern struct task_group root_task_group;
3106 #endif /* CONFIG_CGROUP_SCHED */
3107 
3108 extern int task_can_switch_user(struct user_struct *up,
3109                                         struct task_struct *tsk);
3110 
3111 #ifdef CONFIG_TASK_XACCT
3112 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3113 {
3114         tsk->ioac.rchar += amt;
3115 }
3116 
3117 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3118 {
3119         tsk->ioac.wchar += amt;
3120 }
3121 
3122 static inline void inc_syscr(struct task_struct *tsk)
3123 {
3124         tsk->ioac.syscr++;
3125 }
3126 
3127 static inline void inc_syscw(struct task_struct *tsk)
3128 {
3129         tsk->ioac.syscw++;
3130 }
3131 #else
3132 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3133 {
3134 }
3135 
3136 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3137 {
3138 }
3139 
3140 static inline void inc_syscr(struct task_struct *tsk)
3141 {
3142 }
3143 
3144 static inline void inc_syscw(struct task_struct *tsk)
3145 {
3146 }
3147 #endif
3148 
3149 #ifndef TASK_SIZE_OF
3150 #define TASK_SIZE_OF(tsk)       TASK_SIZE
3151 #endif
3152 
3153 #ifdef CONFIG_MEMCG
3154 extern void mm_update_next_owner(struct mm_struct *mm);
3155 #else
3156 static inline void mm_update_next_owner(struct mm_struct *mm)
3157 {
3158 }
3159 #endif /* CONFIG_MEMCG */
3160 
3161 static inline unsigned long task_rlimit(const struct task_struct *tsk,
3162                 unsigned int limit)
3163 {
3164         return READ_ONCE(tsk->signal->rlim[limit].rlim_cur);
3165 }
3166 
3167 static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
3168                 unsigned int limit)
3169 {
3170         return READ_ONCE(tsk->signal->rlim[limit].rlim_max);
3171 }
3172 
3173 static inline unsigned long rlimit(unsigned int limit)
3174 {
3175         return task_rlimit(current, limit);
3176 }
3177 
3178 static inline unsigned long rlimit_max(unsigned int limit)
3179 {
3180         return task_rlimit_max(current, limit);
3181 }
3182 
3183 #endif
3184 

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